Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Physics Errors
| Question | Answer |
|---|---|
| Do resistors in parallel have the same current? | No, but resistors in series do |
| 2 identical lightbulbs are connected in series to a power source. If another bulb is added, what will be the effect? | The brightness of each individual bulb will decrease |
| A circuit consists of 4 capacitors in series, each one being 12 F, 7 F, 18 F, and 21 F, respectively. What is the order of charges stored by each capacitor from greatest to least? | When capacitors are in series, the charge (Q) stored by each capacitor is the same as the total charge. Q1 = Q2 = Q3 = Q4 |
| What are the sides of a converging lenses? | Convex on both sides |
| A diverging lens is held up in front of a surface. Which of the following statements is true? | the image is always virtual, regardless of the values of do and f. A virtual image can never be projected onto a surface. |
| Which of the following is the unit of the specific heat capacity C? | J/(kg.K) |
| Which of the following is equivalent to 1 Farad? | C2/(N.m) |
| Which of the following is the correct unit of the vacuum permittivity ε0? | C^2 / N • m^2 |
| A ball is rolled off a horizontal table with a velocity, v. If the table has a height, h, and a mass m, which of the following describes the distance the ball will land from the table when it hits the ground? | v × √2h/g |
| A 60 kg skydiver reaches terminal velocity after 12 seconds of freefall. What is the net force on the skydiver once terminal velocity is reached? | 0 N. When the skydiver reaches terminal velocity, his speed becomes constant, therefore a = 0. Fnet = ma, 0 N. |
| The rays of light will move from a medium with a lower index of refraction (air) to a medium with a higher refraction index (water). Will the emerging rays diverge or converge? | Diverge |
| A helium balloon is let go in a room with a speed of 1.3 m/s upward, and it takes the balloon 3.0 seconds to reach the ceiling. If the room's draft has a speed of 0.4 m/s and is directed horizontally, what is the final horizontal displacement? | Use the d = v * t equation -> 0.4 * 0.3 = 1.2 m |
| An object is placed 1 m away from a convex lens that has a focal length of 0.8 m. Which of the following statements about the image is true? | The image will be formed behind the lens |
| A mass, attached to a spring, is oscillating in simple harmonic motion. Which of the following statements regarding this system is true? | Increasing the mass will increase the period of oscillation T = 2pi * sqrt (m/k) |
| Two tuning forks have frequencies of 400 Hz and 410 Hz and the same amplitude. How much time elapses between 2 successive beats? | Difference is 10 Hz. T = 1/fbeat = 1/10 = 0.1s. |
| Electric current can be expressed in which of the following units? | Coulombs/Seconds |
| A ball is kicked at an angle of 30 degrees above the ground. Which of the following statements is true? | The ball’s initial horizontal velocity is greater than its initial vertical velocity. You would do cos(30) vs. sin(30) |
| List the electromagnetic waves from the most energetic to the least energetic | Gamma rays – X-rays – Ultraviolet – Visible light – Infrared – Microwaves – Radio waves |
| A capacitor connected to a battery has two plates, each with a charge Q. If the capacitor is pulled apart such that the distance between the two plates is doubled, while still connected to the battery, what happens to the charge? | The charge is halved, C = episilon * A / D |
| M1 (400 grams) and M2 (200 grams) are attached by a string that is stretched over a pulley. If scissors are used to cut the string above M2, what is the acceleration with which it moves towards the ground? | 9.81 m/s^2, once the scissors are used to cut the string above M2, it will be in free fall. |
| A 50-gram ball is attached to a string on a ceiling, creating a simple pendulum that oscillates with a period of T. Which of the following changes would increase the pendulum period? | Increasing the length of the string |
| An object is located 6 m away from a thin convex lens that has a focal point of 2 m. Where will the image of the object be located? | 3 m behind the lens |
| What must the acceleration of a car (m=1400 kg) be to dissipate 70000 J of energy over 5 m? | 10 m/s^2, W = Fnet * d -> W = m * a * d |
| A +3μC charge is separated from a point charge of unknown magnitude by 3 m. If the force between the two charges is 0.60 N, what is the unknown charge's magnitude? | 2.0 × 10^-4 C |
| A 50 m steel beam undergoes a temperature change from 40°C to 70°C. How much does the length of the beam change if the coefficient of linear expansion of steel is 1.2×10-5/°C? | 1.8 cm |
| Two charges of 0.2 C, charge A and charge B, are separated by a distance of 2 m. What is the magnitude of the force exerted on charge A by charge B? | 9*10^7 N |
| Resistance is a measure of the flow of charge. True or false? | Resistance (R) is the measure of opposition to the flow of charge (false). |
| The figure below shows the amount of heat Q that flows through a window of area A and thickness d in time t. Which of the following changes would decrease Q? | Increase d |
| An object is placed 10 cm in front of a diverging lens with a focal length of 30 cm. Approximate the location of the formed image. | 7.5 cm in front of the lens |
| A box rests on an incline. As the angle of inclination increases, which of the following describes the forces acting on the box? | The force parallel to the ramp increases, and the force perpendicular to the ramp decreases |
| Which of the following represents the unit of the moment of inertia I? | Kg • m2 |
| A wire, W₁, has a resistance R. What is the resistance of a wire that has double the length and double the diameter of W₁? | R/2 |
| On what physical principle are sunglasses based? | Polarization |
| An object is thrown vertically upward. Neglecting air resistance, how does the object's return speed compare to the launch speed if caught at the same location it was launched from? | Vreturn = Vlaunch |
| When you're doing a torque problem with multiple torques, make sure to... | Make one negative and the other positive |
| What is cos 30°? | √3/2 |
| What is sin 30°? | 1/2 |
| What is cos 45°? | √2/2 |
| What is sin 45°? | √2/2 |
| What is cos 60°? | 1/2 |
| What is sin 60°? | √3/2 |
| What is cos 90°? | 0 |
| What is sin 90°? | 1 |
| Is the current the same in resistors in series? | Yes, and in parallel, the voltage would be the same |
| What is the S.I. unit for weight? | kg × m/s2 |
| Three containers open at the top with different shapes are filled with the same liquid to the same height as shown below. Rank the pressures at the bottom of the three containers. | PA = P B = P C |
| A girl pushes a 20 Kg box on a frictionless track with a force of 70 N. Her brother pushes back on the opposite side of the box. If the box accelerates 0.5 m/s2, with what force is her brother pushing back? | Fnet = ma F1 - F2 = ma Solve for F2 |
| Two masses M1 and M2, are initially at rest on a horizontal frictionless surface. A spring is compressed between the two masses. After the spring is released, M1 moves to the left with a speed of v1. What is the speed of mass M2? | Pbefore = 0 0 = -M1v1 + M2v2 M1v1 = M2v2 v2 = M1v1/M2 |
| Kevin, who weighs 800 N on earth, travels to a distant planet with twice the mass and twice the earth's radius. What is the weight of Kevin on the planet? | 400 N |
| bends toward the normal | you're entering a higher value of n |
| bends away from the normal | you're entering a smaller value of n, the value that bends further away from the normal is smaller |
| An object is located 20 cm in front of a converging lens with a focal length of 15 cm. Relative to the object, the image formed by the converging lens is __________. | Real, inverted, larger (trust your knowledge AND your calculations!) |
| A mass is attached to a string on a ceiling and swung back and forth, creating a simple pendulum. At which point does the mass have the most kinetic energy? | A mass attached to a pendulum will have the most kinetic energy when it is at the lowest point of its trajectory. At this point, the string attached to the mass is going to be perpendicular to the ground. |
| An 8 kg wooden crate is being pushed horizontally with a force of 10 N. If the coefficient of static friction between the crate and the floor is 0.25, and the crate is not moving, what is the normal force acting on the crate? | The question states that the crate is not moving, so it can be assumed to be in static equilibrium. In other words, the net force acting on the crate will be equal to zero and forces will be balanced in all directions. Fn = mg |
| Spring (k=2N/m) is compressed 40 cm from its resting position, and the pinball weighs 500 g, what will the velocity of the pinball be after the spring is released? Assume all the energy of the spring is transferred to the pinball. | 0.8 m/s, Set 1/2kx^2 = 1/2mv^2 |
| If a gas in a container absorbs 300 J of heat, has 100 J of work done on it, and then does 60 J of work, what is the change in the gas's internal energy? | Delta U = +340 When the gas does work: W < 0 When the work is done on the gas: W > 0 When the gas absorbs heat: Q > 0 When the gas releases heat: Q < 0 |
| A 60 kg woman is standing in an elevator that is accelerating upwards at a rate of 2 m/s2. What is the normal force acting on the woman as the elevator is in motion? | Fn = mg + ma = 720 N |
| If A<B and C<D, which of the following must be true? | (A – B)(C – D) > 0 |
| What is the SI derived unit for Momentum? | kg·m/s or N·s |
| At how many points in the X-Y plane in the diagram below is the net electric field due to the two charges is zero? Both charges are positive | One in the middle |
| At how many points in the X-Y plane in the diagram below is the net electric field due to the two charges is zero? One charge is negative, the other is positive | No places where it would be zero |
| At how many points in the X-Y plane in the diagram below is the net electric field due to the two charges is zero? Both charges are positive, but different magnitudes | the cancellation point ends up outside the two charges, on the side of the smaller-magnitude charge. There is exactly one such point |
| Water and Benzene are added to a shaped glass tube, as shown below. Which expression below gives the density of Benzene? | If PA = PD, then the formula would be densityB = (densityW * heightW) / heightB |
| Two masses m1 and m2, are dropped from two different heights: h1 and h2. What is the ratio of the times taken by the two masses to reach the ground? (Ignore air resistance) | Square root of (h1/h2) |
| What are the units of momentum? | Kg * m/s |
| A ball is kicked with an initial speed of v0 at an angle θ above the ground, as shown below. Which expression gives the maximum height reached by the ball? (Ignore air resistance) | vo^2sin^2(theta) / 2g Remember that voy = vosin, this would be equivalent to the formula on your sheet! |
| A 50kg girl stands on a wood floor (μk = 0.2, μs = 0.5) and pulls with 50 N of force on a rope attached to the floor. As she pulls, the rope forms a 60° angle with the floor. If she stay at rest, what is the force of friction exerted on girl by the floor? | at rest, the force of friction will only act parallel to the surface the girl is standing on, so direct focus on just horizontal components of force. Also the us * Fn give max static friction, which we don't have. Instead, use Tcos(theta) |
| White light is shone through a prism followed by a red filter. What will an observer see on the other side? | Red light. Coloured filters only allow specific wavelengths of light to pass. A red filter will only allow red light to pass, so an observer will only see the red light on the other side. |
| A ray of light encounters a triangular crystal. What would happen to the path if the crystal’s index of refraction was changed to equal the index of refraction of the medium that surrounds it? | The ray would not be bent at all and travel straight through the crystal |
| Two balls have the same volume. The density of the ceramic ball is 2,500 kg/m3 and the density of the steel ball is 7,800 kg/m3. Each ball is placed into its own identical container filled with water, but neither overflows. What happened? | Both balls have a greater density than water, so both sink. Once each ball is submerged, the water level will rise by an amount exactly equal to the volume of the ball. If the balls have the same volume, the water level must rise by the same amount. |
| A solid sphere made of iron sinks deeper and deeper in a tank of water of constant density. What happens to the buoyant force on the sphere? | Remains Constant |
| Light has a wavelength of 600 nm in air and a wavelength of 500 nm in a transparent medium. What is the index of refraction of the medium? | 1.2, n = wavelength air / wavelength n |
| If red light passes through a green filter, it does not pass through. If blue light passes through the same green filter, what color will the light be? | No light will pass through, When light passes through a colored filter, only the light of the filter's color can pass through. All other colors of light are absorbed or blocked by the filter. |
| A ball is thrown vertically upwards. If it reaches a maximum height of 5 m, what was the ball’s initial velocity? | You would use the vy^2 equation and set vy^2 to 0. The final answer would be 10 m/s. |
| Two forces act on an object. If the object is moving to the left in translational equilibrium, which of the following statements is true? | The object is moving with a constant speed |
| When would a passage qualify for a medical journal? | When it discusses a new discovery made on the topic |
| A ball attached to a string is whirled in a vertical circle as shown below. If the string is cut at point P, what will be the subsequent path of the ball? | It will follow the path of the velocity, but no longer be curved. For example, if it was previously moving upwards left with a curve, it will now be straight up. |
| If a mass is being held suspended by two ropes that make equivalent angles from each side, you would solve for T by... | Tsin(30) + Tsin(30) = Mg |
| Two blocks with masses M1 and M2 are in static equilibrium, as shown below. If M1=20 kg and the coefficient of static friction between the block and the table is 0.5, what is the maximum mass of the hanging block? | Because static equilibrium, the tension in the hanging block must equal the weight, and the tension in the first block must equal the force of static friction. Set up T = M2g T = fs Fn = m1g fs = us * m1g Solve, substitute in M2g equation |
| What are the two types of equilibrium? | Static equilibrium (object at rest) and dynamic equilibrium (object moving at constant velocity). In both cases, net force and net torque = 0. |
| A block is released from the top of a rough ramp angled at 20° with respect to the horizontal as shown below. If the angle of the incline is increased, which of the following statements is true about the force of friction between the block and the ramp? | The force of friction decreases. Fn = mgcos(theta), which goes into fs = us * Fn, so as the angle increases, cos decreases. |
| Elastic Collision | momentum conserved, kinetic energy conserved, objects bounce off one another |
| Inelastic Collision | momentum conserved, kinetic energy not conserved, objects may bounce (regular inelastic) or stick together (perfectly inelastic) |
| Which of the following is the correct unit of the impulse experienced by an object that is acted upon by force? | N.s |
| Wavelength and energy relationship | Inverse |
| A 4 kg rock is released from a height of 6 m above the ground and allowed to free fall. If air resistance is ignored, how much kinetic energy will the rock have as it touches the ground? | 240 J. Kinetic energy gets converted to potential. mgh = (4)(10)(6) = 240. |
| n formula in relation to height | n = actual depth / apparent depth |
| Two plastic balls of different densities (ρ1>ρ2) and equal volumes are held underwater, then released. The two plastic balls accelerate upwards. Which of the following statements is true about the acceleration of both balls? | a1 < a2 |
| Ray diagrams for converging vs. diverging | Converging will group together (aim down and bunch together), while diverging will spread apart and up (diverge) |
| A boy is sitting on a Ferris wheel that makes one full rotation every 30 seconds. What is the angular velocity of the Ferris wheel in rad/s? | (pi/15) * (rad/s) One full rotation of the wheel is equal to 360 degrees or 2π rad, so ω = theta / t = 2pi/30 = pi/15 * (rad/s) |
| Wavelengths of Colors (Shortest to Longest) | Violet < Blue < Green < Yellow < Orange < Red |
| A block of mass (m) is thrown off a building horizontally with a speed v0 from a height (h) as shown below. What is the vertical speed of the block right before it hits the ground? | vy =√2gh |
| Horizontal Height Equations | h = (1/2)gt^2 t = √(2h/g) |
| A 2 kg block is released from rest and falls vertically onto a spring located 8 m below. If the spring has a spring constant of 20 N/m, how much will the spring be compressed once the block comes to a halt? | Set mgh = 1/2kx^2 and solve to get 4 m. |
| The graphs of a net force (F) on an object moving in a straight line as a function of the displacement are shown below. Which graph represents the net force that will cause the greatest change in the momentum of the object? | Fnet that will cause the greatest change in momentum will cause the greatest change in KE. Change in KE of an object is equal to the net work done on the object and is equivalent to the area under the curve of F versus D. Find the largest curve |
| Energy vs Power units | Energy uses Joules, Power uses Watts |
| A 6-meter plank of uniform density and a mass of 40 kg rests on the top of a cliff with 1.5 m extended out as shown below. How far can a 50 kg child walk past the edge of the cliff on the plank before the plank starts to tip over? | Just before the plank starts to tip, torque = 0. So, M1g(1.5) = M2g(x) with x being the amount that the boy can walk. Solve for 1.2 m. |
| Two traveling waves of equal frequencies, one of amplitude 6 cm and the other of amplitude 10 cm superimpose in a single medium. Which of the following describes the amplitude (A) of the resulting wave? | 4 cm<A<16 cm, because we don't know whether they're combing destructively or constructively, we'd use the difference between the max and minimum. |
| When two waves interfere constructively, the resulting amplitude is | the sum of the amplitudes of the two waves. |
| When two waves interfere destructively, the resulting amplitude is | the difference of the two amplitudes. |
| 600 J of heat is applied to a gas confined in a container. The gas then performs 250 J of work on its surroundings. Which of the following values is closest to the change in internal energy experienced by the gas? | 350 J, Q is pos and W is neg |
| What is the total current delivered by the battery in the circuit below when the capacitor is fully charged? | When the capacitor in the circuit is fully charged, it acts as an open circuit. No more current flows through the capacitor. The circuit is equivalent to: I = V/Rtotal -> Rtotal |
| A rocket orbits at 270 km above Earth’s surface. If the Earth has a radius of 6400 km and weighs 6 × 1024 kg. Which of the following represents the velocity at which the rocket is travelling? | v = sqrt (Gm earth / 6.67*10^6 m) You would set G(mrocket * mearth)/r^2 = mrocketvrocket^2 / r |
| A sound wave travels through air with a speed of 340 m/s and through glass with a speed of 3400 m/s. What happens to the wavelength of a sound wave as it travels from air to glass? | It increases by a factor of 10. wavelength glass / wavelength air = v glass / v air |
| Which of the following graphs correctly represents the acceleration of an object moving with a constant velocity? | If it's an a vs. t graph, then the line would be straight and at 0. |
| An Ampere-hour is a unit of which of the following physical quantities? | Charge |
| 3 blocks M, N, and P rest on a table as shown below. The weights are 40, 50, 80. What is the force exerted by block M on block N? | 40 N |
| 3 blocks M, N, and P rest on a table as shown below. The weights are 40, 50, 80. What is the force exerted by block P on block N? | 90 N M and N combined exert a force of 90, so P would give that back as an opposite reach. |
| An ideal battery of constant voltage V supplies current to a circuit that has total resistance R. If the total resistance is doubled, what happens to the rate at which the energy is dissipated by the circuit? | It halves |
| A block is released from the top of a rough incline with an initial speed of 2 m/s. The coefficient of kinetic friction between the block and the incline is 0.6. How much work is done by the normal force when the block reaches the bottom of the incline? | 0 J. At the bottom, the normal force is perpendicular to the block’s displacement (θ = 90°). So, 0. Tip: the angle in this one was 37, which would be unsolvable, which sometimes mean it's 0. |
| What is the force of gravity equal to? | mg |
| The figure below shows a spring attached to a ceiling. If the mass attached to the spring is doubled, how will the mass equilibrium’s position and frequency be affected? | Equilibrium position: Increased by a factor of 2. Frequency: Decreased by a factor of √2. At equilibrium, mg = kx and f = 1/pi * sqrt (k/m) |
| A net torque applied to a rigid body produces __________. | Angular acceleration Remember torque net = Ia |
| An object of height 2 cm is placed 30 cm in front of a converging lens with a radius of curvature of 20 cm. Which of the following is true about the image formed by the lens? | Real, inverted, height = 1 cm |
| 3 balls with identical masses m are attached to a vertical shaft S by 3 rigid massless rods and are free to rotate about S. What is the total moment of inertia of the 3 balls? First distance is 1, second is 2, and third is 3. | I = 14M kg.m2 |
| Which of the following is an example of a longitudinal wave? Vibrations on the string of an instrument A tsunami wave An electromagnetic wave A sound wave | A sound wave |
| Transverse waves + examples | The direction of propagation of the wave is perpendicular to the direction of propagation of the particles of the wave. Electromagnetic Waves, Waves on a String |
| Longitudinal waves + examples | The direction of propagation of the wave is parallel to the direction of propagation of the particles of the wave. Sound waves |
| Tsunami waves | These are both transverse and longitudinal. They are called surface waves. |
| A plate is held upright between a screen and a candle as shown in the diagram below. A shadow is cast on the screen. What will happen to the shadow as the plate is moved toward the candle? | The shadow will get larger. The plate blocks the light and creates a shadow on the screen. As the plate is brought toward the candle, it will block an increasing amount of light, resulting in a larger shadow on the screen. |
| Two men are pushing on a box horizontally from opposite sides. If one man is pushing with a force of 2 N and the other is pushing with a force of 5 N, what is the magnitude of the net force experienced by the box? | 3 N |
| Rank the following materials, from lowest to highest, in terms of their indices of refraction: water, glass, air, diamond. | Air, water, glass, diamond |
| A system consisting of a mass m = 20 kg and 2 pulleys are shown below. The 2 pulleys are frictionless and massless. What minimum force F is required to lift the mass? | For problems like this, you can find the value of T for the first pulley based on how many strings it has, then equate that to the force for the second, free-hanging one. |
| A solid cylinder with mass m is dropped on top of an identical cylinder initially rotating at ωi = 10 rad/sec and sticks to it. If we ignore frictional losses, what is the combined angular speed of the two cylinders? | Iwi + Iwi = (I1 + I2)wf -> 5 rad/sec Remember that things at rest will not have a value for w! |
| If the x- and y-components of a vector are doubled, what happens to the magnitude of the resulting vector? | The magnitude increases by a factor of 2 |
| Two charged glass balls are brought a distance l from each other. The force exerted on ball A by ball B is 3 μN left. When the distance is decreased, the force on ball A is 6 μN left. Which of the following could be the sign of the charges? | Ball A: Negative, Ball B: Negative. Because the force exerted on A by B is to the left, the force exerted on B by A will be of the same magnitude to the right by Newton’s third law. The forces are repulsive, so the sign charges will be the same. |
| An object is placed 50 cm in front of a plane mirror. How far is the object from the image? | 100 cm. Read what they're asking CAREFULLY. Do = 50 cm, so Di would also equal 50 cm. However, if you're asking object from image, then it would be 50 + 50. |
| A 40 kg block resting on the ground is lifted upwards with a force of 10 N. The block remains at rest. What is the magnitude of the normal force acting on the block? | 390 N. Since the block remains at rest, the net force acting on the block is zero. Fn + Fa - Fg = 0. Fn = Fg - Fa. |
| Two waves on identical strings have wavelengths in a ratio of 2:1. If their speed is the same, what is the ratio of their frequencies? | 1:2 |
| The specific heat capacity of aluminum is 900 J/kg ℃ and the specific heat capacity of iron is 450 J/kg ℃. If two samples of the two metals with the same mass absorb 85 KJ, Which of the following is true about the change in the temperature? | Delta Tiron = 2 Delta Taluminum Remember that the one with the higher c will need more heat to reach the same temperature! |
| A ball with a mass of 2 kg is attached to a 50 cm string being swung in a horizontal circle. If the ball completes one revolution in 2 seconds, what is the tension in the string? | pi^2 N. v = 2pir / t -> 2pi(0.5) / 2 -> pi /2 * m/s Submit that into the original equation |
| A mass m attached to a spring with a spring constant K oscillates in a simple harmonic motion with an amplitude of A. What is the angular frequency ω? | w = sqrt (k/m) Do NOT include the A, because that would make it vmax instead. |
| A pencil is placed in front of a flat mirror. Which of the following statements regarding the image formed is true? | A virtual image will be formed behind the mirror. Plane mirrors (flat mirrors) will only produce virtual images behind the mirror. This is because plane mirrors do not converge light rays directed at them. |
| Interference of light is evidence that __________. | Light is a wave phenomenon |
| Double-slit experiment | Thomas Young showed that light behaves like waves. When a beam of light passed through two thin parallel slits, dark and bright fringes on the screen showed that the two slits caused light waves to interfere with each other. |
| sin(180) = | 0. This tells you that the largest torque will always be made by sin(90). |
| The ratio of the wavelength of light beam I to the wavelength of light beam II is 3:2. What is the ratio of their energies? | 2:3 |
| The speed of a 10 N object sliding across an icy horizontal surface decreases at a rate of 0.8 m/s2. What is the coefficient of kinetic friction? | 0.08. The only force acting on the object as it slows down is the frictional force. -uk * Fn = ma. Find m by doing W/g -> 10/10 = 1 kg. Fn = 10. Solve for uk. |
| A 5 kg box is being pushed horizontally at a constant velocity of 5 m/s. What is the net force acting on the box? | An object at rest or moving with a constant velocity will not experience any acceleration. Since the box is moving at a constant velocity, the net force acting on it will be equal to zero. |
| If light travels from air (n1 = 1.00) into water (n2 = 1.33), which of the following would we expect to occur? | There would be no critical angle. Light traveling from a medium with a lower index of refraction to a higher index of refraction will result in no critical angle. |
| In an isobaric process, when the volume expands, is work positive or negative? | Isobaric process: the work done by the system is negative. |
| In an isobaric process, when the volume contracts, is work positive or negative? | Isobaric process: the work done by the system is positive. |
| conservative force | a force where the total work done on an object depends only on the initial and final positions, regardless of the path taken. Ex: gravitational force, elastic force |
| nonconservative forces | force whose work depends on the path taken. Ex: friction, tension |
| The wheel of a car with a radius r = 0.5 m starts from rest then travels with a constant angular acceleration α = 2 rad/s2. What is the approximate angle θ through which the wheel has rotated after t = 0.2 s? | 0.04 rad |
| An 8 m long pipe is closed at one end. The speed of sound in the pipe is 320 m/s. What is the frequency of the second overtone of the pipe? | Where n = 1, 3, 5, … (odd integers). For the second overtone, which is the 5th harmonic, n = 5. First would be 3. |
| A solid object is fully submerged in water, experiencing a buoyant force of 50 N. The object is then submerged in an oil with a density that is 80% that of water. How does the buoyant force in the oil compare to the buoyant force in water? | The buoyant force in oil is 40 N. |
| Wire A has twice the diameter of wire B. Both wires are subjected to the same tensile force. How do the stress and strain in wire A compare to the stress and strain in wire B? | Wire A experiences one-fourth the stress and one-fourth the strain as wire B. Remember that area is found by pi*(r)^2. Also since both wires are made of the same material, they have the same Young’s modulus. |
| law of conservation of electric charge | states that no net electric charge can be created nor destroyed, and any process producing charge creates equal amounts of positive and negative charge. |
| At maximum displacement (amplitude): | The velocity is zero because the object momentarily stops before changing direction. The acceleration is at a maximum because the object experiences the strongest restoring force. |
| At the equilibrium position: | The velocity is at its maximum because the object is moving the fastest. The acceleration is zero because the restoring force is zero. |
| A metal cube with a mass of 200 g is fully submerged in water. If the specific gravity of the metal is 4, what is the volume of the cube? | 50 cm^3. Because SG = pmetal/pH2O -> pmetal = SG * pwater, then substitute in the values to get volume. |
| In a cooking class, you are using a pressure cooker to prepare a stew. The cooker is sealed tightly during cooking. How would you classify this cooking setup in terms of its interaction with the environment? | A closed system. This setup typifies a closed system, where energy can transfer but matter cannot, making it distinct from both isolated systems (no exchange of energy or matter) and open systems (exchange of both energy and matter). |
Created by:
smurtab