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MCAT Physics Kaplan
Kaplan Physics flashcards
Question | Answer |
---|---|
What are the units of each of the following? 1. Length 2. Mass 3. Force 4. Time 5. Work & Energy 6. Power | 1. Meter (m) 2. Kilogram (kg) 3. Newton (N) 4. Second (s) 5. Joule (J) 6. Watt (W) |
Give the prefix and abbreviation for each of the following powers. 1. 10⁹ 2. 10⁶ 3. 10³ 4. 10ˉ² 5. 10ˉ³ 6. 10ˉ⁶ 7. 10ˉ⁹ 8. 10ˉ¹² | 1. Giga (G or B) 2. Mega (M) 3. Kilo (k) 4. Centi (c) 5. Milli (m) 6. Micro (u) 7. Nano (n) 8. Pico (p) |
Put the following in Standard scientific notation. 1. 103 2. 123456 3. 103 × 10² 4. 0.103 × 10ˉ¹² 5. (2 × 10⁶)(9 × 10²) 6. (6 × 10³)² 7. (3 × 10²) + (3 × 10³) | 1. 1.03 × 10² 2. 1.23456 × 105 3. 1.03 × 10⁴ 4. 1.03 × 10ˉ⁵ 5. 1.8 × 10⁹ 6. 3.6 × 10⁷ 7. 3.3 × 10³ |
trigonometric functions: 1. sin θ = 2. cos θ = 3. tan θ = | 1. sin θ = opposite/hypotenuse 2. cos θ = adjacent/hypotenuse 3. tan θ = opposite/adjacent |
What are the sin and cos values for the following angles? 1. 0˚ 2. 90˚ 3. 30˚ 4. 60˚ 5. 45˚ 6. 180˚ | sin; cos 1. 0; 1 2. 1; 0 3. .5; .866 4. .866; .5 5. .7; .7 6. 0; .1 |
What is the difference between a scaler quantity and a vector quantity? | a scaler quantity has magnitude but no direction. A vector quantity has magnitude and direction. |
Are the following scaler or vector quantities? distance; force; velocity; speed; mass; displacement; | Distance, speed and mass are scalar quantities. Displacement, velocity, and force are vector quantities |
True or False. The sum of two vectors is the resultant of the vectors. | true |
A person walks 2 miles north and then turns around and walks 3 miles south. Total time elapsed = 1 hr. 2. Distance (d) = 3. displacement ∆x = 4. Average velocity (v) = 5. Average speed (s) = | 1. Distance = 2 + 3 = 5 2. Displacement = 2miles (N) + (-3) miles (S) = 1 mile (S) 3. Average velocity = 1 mile / 1hr = 1 mile/hour (S) 4. Average speed = 5 miles / 1 hour= 5 miles/hour |
1. Average acceleration (ā) = For a body under constant acceleration: 2. v= 3. ∆x= 4. v²= 5. avg v= | 1. a = ∆v/∆t 2. v=v₀ + at 3. ∆x=v₀t + at²/2 4. v²=v₀² + 2a(∆x) 5. avg v= (v₀ + v/2) |
Is weight a scalar or a vector? What is the formula for calculating weight? | weight is a vector quantity. weight = (mass)(gravity |
What are Newton's Three Laws of Motion? | 1. A body in motion with constant velocity in a straight line path or at rest will remain that way unless a net force acts upon it. 2. Force = (mass)(gravity) = ma 3. To every force there is always an equal and opposite force. |
What are the formulas for the initial horizontal and vertical velocities of a projectile launched with a speed v at an angle of theta to the horizontal? | the horizontal velocity is vcosθ, and the vertical velocity is vsinθ |
What does the total horizontal distance, x, traveled by a projectile equal? | x=(initial horizontal velocity)(time in air) |
What is the formula for gravitational force? | F = Gm₁m/r² |
If the distance between two objects is doubled, by how much is the force of gravity increased or decreased? | The force would decrease by a factor of 4 (2²) |
True or False. A body in translational equilibrium has a net force moving it at a constant velocity. | False, a body in translational equilibrium has not net force acting on it. |
If a lever arm is halved, by how much does the torque increase or decrease? | the torque would decrease by half. |
What is the formula for calculating torque? τ = | τ = rFsinθ (r = distance between force and axis of rotation) |
When calculating torque, which rotation direction is considered positive and which is considered negative? | counterclockwise is positive; clockwise is negative |
True or False. For rotational equilibrium to occur, the sum of all torques acting on a body must be zero. | True. |
What is translational motion? | Translational motion is defined as motion in which the position of the object's center of mass changes as a function of time. |
What is the formula for the force of static friction? | f≤μN |
What is the formula for force of kinetic friction? | f=μN |
What is the formula for centripetal acceleration (for a body in uniform motion)? a= | a = v²/r |
What is the formula for centripetal force (for a body in uniform circular motion)? F= | F=mv²/r |
(T/F) For a planet orbiting a star the centripetal force is equal to the gravitational force. | True. |
What is the formula for work? W= | W=Fd |
What is the unit of work? | The unit for work is the Joule (⌡) (N•m) |
What is the formula for Power? P= | P= W/t |
What is the unit of power? | The unit of power is the Watt (1 Joule/sec) |
What is the formula for kinetic energy? KE= | KE=mv²/2 |
What are the units of KE? | the units of KE are joules. |
What is the formula for gravitational potential enrgy? U= | U=mgh |
What are the units of gravitational potential energy? | The units of gravitational potential energy are joules |
(T/f) The total mechanical energy of a body is the sum of its kinetic and potential energies. | True |
Is total mechanical energy constant if the only forces that act on a body are conservative (E=K+U=constant)? | Yes, E=K+U=constant |
What is the change in energy of a system if only conservative forces act upon it? | If only conservative forces act on a body, then ∆E=0 |
What is the formula for momentum? p= | p=mv |
What is the formula for impulse? J= | J= (Force)(time) = Ft = mv-mv₀ = ∆p |
Is kinetic energy conserved in a completely elastic collision? | Yes, kinetic energy is conserved in a completely elastic collision. |
(T/F) Net external force must equal zero for conservation of momentum to occur. | True. |
What is the formula for the center of mass for two masses, m₁ and m₂, lying along the x-axis at points x₁ and x₂? X= | X = (m₁x₁ + m₂x₂)/(m₁ + m₂) |
(T/F) Momentum is not conserved in an inelastic collision. | False, momentum is conserved in both elastic and inelastic collisions |
What are the temperatures in Kelvin and Celsius for the following? 1. Absolute zero 2. Freezing point of water 3. Boiling point of water | K; °C 1. 0; -273 2. 273; 0 3. 373; 100 |
What is the formula for converting Kelvin to Celsius? Tc= | Tc = Tk-273 |
What is the formula for thermal expansion of a solid? ∆L = | ∆L = L₀α∆T (α = coefficient of linear expansion) |
What is the formula for volume thermal expansion of a liquid or solid? ∆V = | ∆V = V₀β∆T (β = coefficient of volume expansion) |
What type of transfer involves the direct transfer of energy from molecule to molecule through molecular collisions? | Conduction |
What type of heat transfer involves the transfer of energy by electromagnetic waves? | Radiation |
What type of heat transfer involves the physical motion of heated material? | Convection |
What are the units of heat? | The units of heat are calorie, Btu, and Joule. |
What is the difference between calorie and Calorie? | A Calorie is a nutritional term and is equal to 1000 calories. |
What is the formula relating heat gained and temperature changed? Q = | Q = (mass)(specific heat)(∆T) = mc∆T |
What is heat of fusion? | Heat of fusion is the amount of energy required for a phase change from solid to liquid |
What is heat of vaporization? | Heat of vaporization is the amount of energy required for a phase change from liquid to gas. |
What is the formula for heat gained or lost during a phase change ? Q = | Q = (mass)(Heat of transformation) = mL |
What is the SI unit for Pressure? | The SI unit of pressure is the Pascal. |
What is an isobaric process? | An isobaric process is a process done at constant pressure. |
What is the formula for work (given an isobaric process)? W = | W = (Pressure)(∆Volume) = P∆V |
What is the formula for the First Law of Thermodynamics? ∆U = | ∆U = (heat energy gained) - (work done by a system) |
(T/F) Heat flow out of a system is (+) and heat flow into a system is (-). | False, heat flow out of a system is (-) and heat flow into a system is (+). |
What is an adiabatic process? | An adiabatic is one in which no heat flows from the system to its surroundings (or vice versa). |
What is the Second Law of Thermodynamics? | The Second Law of Thermodynamics states that the entropy of a closed system will either increase or remain unchanged. |
Does a totally reversible process increase the entropy of the universe? What about an irreversible process? | A totally reversible process does not increase the entropy of the universe, but an irreversible process does. |
(T/F) Unlike charges attract and like charges repel. | True. |
What is the formula for Coulomb's Law? F = | F = (Constant)(charge 1)(charge 2)/(distance)² F = kq₁q₂/r² |
If the distance between two charged objects is tripled, by how much does the electrostatic force change? | The electrostatic force would decrease by a factor of 9. |
If the distance between two charged objects is halved, by how much does the electrostatic force change? | The electrostatic force would increase by a factor of 4. |
What is the formula for an electric field at a distance (r) from a charge (q)? E = | E = kq/r² |
In which direction will an electric field vector point around a positive charge? | The field vectors point away from a positive charge. |
In which direction will an electric field vector point around an a negative charge? | The field vectors point toward a negative charge. |
What is the formula for the force that a charge (q) experiences in an electric field (E)? F = | F = qE |
What are the units of an electric field? | The units of an electric field are (Newtons / Coulomb) or (Volts/meter). |
What are the units of voltage? | The units of voltage are Volts or (Joules / Coulomb) |
What is the formula for electric potential given a charge (q) at a distance of (r)? V = | V = kq/r |
What is the potential difference between two points on an equipotential line? | The potential difference is zero. |
What is the formula for electric potential energy? U = | U = qV |
What happens to a dipole if it is placed in a uniform electric field? | The dipole will align with the electric field lines. |
How much work is done on a charge if it is moved in a straight path between two equipotential lines? | No net work is done. |
What are the units of a magnetic field? | The units of a magnetic field are the Tesla. Sometimes the units are given in Gauss. 1 Tesla = 10⁴ Gauss |
What is the formula for force on a moving charged particle in a magnetic field? F = | F = (charge)(velocity)(magnetic field)(sin θ) = qvBsinθ |
What force will a stationary charged particle in a magnetic field experience? | A stationary particle will experience no force in a magnetic field. |
What force will a moving charge experience if it travels parallel or antiparallel to a magnetic field? | No force will be experienced if the charge moves parallel or antiparallel to a magnetic field. |
What are the units of current? | The units of current are Amperes. 1 A = 1 Coulomb/sec |
What is the formula for current? i = | i = ∆q/∆t |
What is the formula for the force on a current carrying wire in the presence of a magnetic field? F = | F = (current)(length)(magnetic field)(sinθ) = iLBsinθ |
A proton moving in a magnetic field experiences a force towards the top of the page. An electron moving in the same direction as the proton experiences a force in which direction? | Towards the bottom of the page. |
A proton moves towards the top of the page in a region where a magnetic field is directed into the page. What is the direction of the magnetic force? | Towards the left. |
A long straight wire carries a current directed towards the top of the page. What is the direction of the magnetic field on the left side of the wire? | The field points out of the page. |
What is the formula for the magnetic field created by a long straight wire? B = | B = (permeability of free space)(current)/(2π)(distance from wire) = μ₀i/2πr |
A magnetic field is created by a loop of wire. What is the formula for the magnetic field at the center of the loop? B = | B = μ₀i/2r (r = radius) |
(T/F) In DC current, the charge flows in one direction only. | True. |
(T/F) In AC current, the charge flows in one direction only. | False, in AC current, the flow of charge changes direction periodically. |
(T/F) By convention, the direction of current is the direction in which negative charge would flow. | False, the direction of current is the direction in which a positive charge would flow. |
What is the formula for Ohm's Law? V = | Volts = (current)(resistance) = iR |
How do the following affect the resistance of a conductor? 1. Increased length. 2. Increased cross-sectional area. 3. Increased temperature. 4. Increased resistivity (ρ). | 1. As length increases, so does resistance. 2. As cross-sectional area increases, resistance decreases. 3. As temperature increases, resistance typically increases. 4. As resistivity increases so does resistance. |
What is the formula for electrical potential? P = | P = (current)(voltage) = iV = i²R = V²/R |
What is the formula for calculating resistance given resistors in a series? Rs | Rs = R₁ + R₂ + R₃ + ... + Rn |
What is the formula for calculating resistance given resistors in parallel? Rp = | 1/Rp = 1/R₁ + 1/R₂ + 1/R₃ + ... + 1/Rn |
What is Kirchoff's 2nd Law? | Kirchoff's 2nd Law states that the sum of the voltage drops around a circuit loop equals the sum of the voltage rises around the loop. |
If 7A of current flow into a three way junction and 3A leave via one of the routes, how much current leaves via the other? | 7A - 3A = 4A |
What is the formula for capacitance? C = | C = charge stored on a plate/potential difference between the plates = Q/V |
What are the units of capacitance? | The units of capacitance are Farads. 1 Farad = 1 Coulomb / Volt |
What is the formula for the electric field between the plates of a capacitor? E = | E = potential difference between the plates/ distance between the plates = V/d |
(T/F) As plate area increases capacitance increases proportionally. | True. |
Does the introduction of a dielectric material between plates of a capacitor increase or decrease the capacitance? | A dielectric material increases the capacitance. The new capacitance (C') = CK, where K = dielectric constant. |
What is the formula for calculating capacitance given capacitors in series? Cs = | 1/Cs = 1/C₁ + 1/C₂ + 1/C₃ + ... + 1/Cn |
What is the formula for calculating capacitance given capacitors in parallel? Cp = | Cp = C₁ + C₂ + C₃ + ... + Cn |
For AC current, what is the formula for calculating Irms? | Irms = Imax/√2 |
For AC current, what is the formula for calculating Vrms? | Vrms = Vmax/√2 |
What is the formula for Hooke's Law? F = | F = -(spring constant)(displacement from equilibrium) F = -kx |
What are the formulas for angular frequencies of a mass on a spring and of a pendulum (SHM)? ω = | ω = √k/m (spring); √g/L (pendulum) |
What is the formula for kinetic energy (SHM)? K = | K = 1/2 (mass)(velocity)² = mv²/2 |
What is the formula for potential energy (SHM)? U = | U = 1/2 (spring constant)(displacement)² = kx²/2 U = (mass)(gravity)(height) = mgh (pendulum) |
(T/F) For an object in SHM, E = K+U = constant | True. |
When is an object's kinetic energy greatest (SHM)? | Kinetic energy is greatest at the equilibrium point. |
When is an object's potential energy greatest (SHM)? | Potential energy is greatest at maximum displacement from equilibrium. |
(T/F) For an object in SHM, frequency = 1/period. | True. |
What are the formulas for the period of a mass on a spring and of a pendulum in SHM? T = | T = 2π√m/k (spring) = 2π√L/g (pendulum) |
Describe particle oscillation in a transverse wave. | Particles oscillate perpendicular to wave motion in a transverse wave. |
Describe particle oscillation in a longitudinal wave. | Particles oscillate along the direction of wave motion in a longitudinal wave. |
What is the formula relating the speed of a wave to its frequency (f) and wavelength (λ)? v = | v = fλ |
(T/F) A sinusoidal wave crosses its equilibrium point every 90°. | False, a sinusoidal wave crosses its equilibrium point every 180°. |
(T/F) The fundamental harmonic has the longest wavelength and thus the smallest frequency of all the harmonics. | True. |
(T/F) The higher the harmonic, the greater the wavelength. | False, the higher the harmonic, the shorter the wavelength. |
What is a node? | A node is a point in a standing wave that remains at rest. |
What is an anti-node? | An anti-node is a point in a standing wave that fluctuates at maximum amplitude. |
Two waves that are 180° out of phase exhibit which type of interference? | Destructive interference. |
Two waves that are 720° out of phase exhibit which type of interference? | Constructive interference. |
(T/F) When two waves are out of phase by 180° and interfere with each other, the resulting displacement is always zero. | False, the resultant displacement is only zero when two waves have equal amplitudes. |
What is the formula for sound intensity? I = | I = power/ area (P/A) |
What is the beat frequency for two frequencies which differ by 4 Hz? | 4 HZ. This is a trick question-the beat frequency is equal to the difference of the two frequencies. |
(T/F) The observed frequency from a source emitting a sound is higher if the source is moving toward a stationary observer. | True. |
(T/F) Standing waves in pipes open at both ends have nodes at the ends. | False, standing waves in pipes open at both ends have antinodes at the ends. |
(T/F) Standing waves in strings fixed at both ends have nodes at the ends of the strings. | True. |
(T/F) Higher harmonics of standing waves in open pipes have higher wave speed than lower harmonics. | False, the wave speed of all harmonics is the same. |
What is the equation for density? ρ = | ρ = m/v |
What is the density of H₂0? | ρ(water) = 1000 kg/m³ = 1g/cm³ |
What is specific gravity? | Specific gravity is the ratio of a substance's density to the density of water. |
What is the formula for calculating pressure? P = | P = Force/Area = F/A |
What is the formula for absolute pressure in a liquid? | P = (surface pressure) = (ρ)(gravity)(depth) = P₀ + ρgh |
What is gauge pressure? | Gauge pressure is the pressure in excess of atmospheric pressure. |
(T/F) Pascal's principle states that a change in pressure applied to an enclosed fluid is transmitted undiminished to every portion of the fluid and to the walls of the container. | True. |
What is the formula for buoyant force? Fb = | Fb = ρgV, where ρ is the density of the fluid and V is the volume of the object immersed in the fluid. |
Given a pipe of varying cross-sections, how do fluid velocity and cross-sectional area relate throughout the pipe? | A₁V₁ = A₂V₂ (volume flow rate is constant) |
(T/F) According to Bernoulli's Equation, as fluid velocity increases, absolute pressure decreases. | True. |
What is viscosity? | Viscosity is the measure of the internal friction of a fluid. |
Does the viscosity of a liquid generally increase or decrease as temperature rises? | An increase in temperature generally causes the viscosity of a liquid to decrease. |
What is the speed of electromagnetic wave (light) in a vacuum? | The speed of light in a vacuum is (3 × 10⁸) m/s. |
What type of image do plane mirrors create (real or virtual)? | Plane mirrors always create virtual images. |
How are focal length and radius of curvature related? | Focal length = radius of curvature/2 = r/2 |
What is the formula relating object distance (o), image distance (i), and focal length (f)? | 1/o + 1/i = 1/f =2/r |
Does virtual image have a positive (+) or negative (-) image distance? | A virtual image has a negative distance. |
If an image is in front of a mirror, is it real or virtual? | An image is in that is in front of a mirror is real. |
Does a real image have a positive (+) or negative (-) image distance? | A real image has a positive image distance. |
What is the formula for magnification? m = | m = - image distance/object distance = - i/o |
(T/F) A negative (-) magnification signifies an upright image. | False, a (-) magnification signifies an inverted image and a (+) magnification signifies an upright image. |
What type of image does a diverging (convex) mirror create? | A diverging mirror always creates a virtual upright image. |
What type of image does a converging (concave) mirror create when the object is placed beyond the focal point? | An object beyond the focal point produces a real inverted image in a converging mirror. |
What type of image does a converging (concave) mirror create when the object is placed inside the focal point? | An object inside the focal point produces a virtual upright image in a converging mirror. |
Does a convex mirror have a positive or negative focal length (or radius of curvature)? | A convex mirror has a negative (-) focal length and radius of curvature. |
Does a concave mirror have a positive or negative focal length (or radius of curvature)? | A concave mirror has a positive (+) focal length and radius of curvature. |
What is the formula for index of refraction? n = | n = speed of light in a vacuum/speed of light in a medium = c/v |
What is the formula for Snell's Law? | n₁sinθ₁ = n₂sinθ₂ |
Under what conditions will light undergo total internal reflection? | Total internal reflection will occur when light travels from a medium with higher index of refraction to a medium with a lower index of refraction and with an angle of incidence greater than the critical angle. |
Does a converging lens have a positive (+) or negative(-) focal length? | A converging lens has a positive (+) focal length. |
Does a diverging lens have positive (+) or a negative (-) focal length? | A diverging lens has a negative (-) focal length. |
(T/F) The "real" side of a lens is the side opposite that from which light originates. | True. |
What type of image does a diverging lens produce? | A diverging lens produces a virtual upright image. |
What type of image does a converging (convex) lens create when the object is placed beyond the focal point? | An object beyond the focal point produces a real inverted image in a converging lens. |
What type of image does a converging (convex) lens create when the object is placed inside the focal point? | An object inside the focal point produces a virtual upright image in a converging lens. |
What are the units of power for a lens? | Diopters are the units of lens power (when f is measured in meters). |
What is the formula for calculating lens power? P = | P = 1/f |
(T/F) The splitting of white light in a prism is an example of dispersion. | True. |
What is diffraction? | Diffraction is the spreading out of light as it passes through a narrow opening. |
(T/F) Light waves can constructively and/or destructively interfere with each other. | True. |
What is polarized light? | Polarized light is light in which the electric fields of all the waves oriented in the same direction. |
Is the energy of a proton dependent on frequency or on amplitude? | The energy of a photon is dependent on frequency. |
What is the formula for calculating the energy of a photon? E = | E = (Plank's constant)(frequency) = hf |
What is the photoelectric effect? | The photoelectric effect is the phenomenon whereby electrons are emitted by a metal that is exposed to light of sufficiently high frequency. |
(T/F) Photon energy increases when wavelength increases. | False, Photon energy decreases as wavelength increases, as seen in the formula E = hc/λ. |
What is the threshold frequency (photoelectric effect)? | The threshold frequency is the minimum frequency of light that will cause the emission of an electron. |
(T/F) The excess energy of a photon is converted to extra kinetic energy of the emitted electron. | True. |
What is the formula for calculating the kinetic energy of an emitted electron? K = | K = hf - W; |
How many electrons will be emitted when using light with frequency below the threshold frequency? | None. |
(T/F) The electron Volt (eV) is a unit of energy. | True. |
What happens to an electron that absorbs a photon? | An electron that absorbs a photon will jump to a higher energy level. |
What happens when an electron jumps from a higher energy level to a lower energy level (orbit)? | An electron that jumps from a higher energy level to a lower energy level will emit a photon whose energy equals the difference in energy between the two levels. |
What is the minimum energy level needed to ionize an electron in a state with energy -10 eV? | 10eV. (Ionization means producing a free electron and free electrons have energy greater than or equal to zero.) |
What is a nucleon? | A nucleon is a proton or a neutron. |
What does an atom's atomic number represent? | Atomic number represents the number of protons in the atom's nucleus. |
What does an atom's mass number mean? | Mass number represents the number of (protons + neutrons) in the atom's nucleus. |
What is an isotope? | An isotope is a variant of an atom with the same number of protons but with different number of neutrons. |
What does an atom's atomic weight represent? | Atomic weight represents the weighted average of the masses of the naturally occurring isotopes of an element. |
What is mass defect? | Mass defect is the difference between the mass of a nucleus and the sum of its constituents (nucleons). |
What formula is used for calculating binding energy? | Energy = (mass defect)(speed of light)² = ∆mc² |
What is the name of the process for combining smaller nuclei into larger nuclei? | Fusion is the combining of smaller nuclei to create larger nuclei. |
What is nuclear fission? | Fission is the splitting of atomic nuclei. |
If the half-life of an isotope is 2 years, how much of the original isotope will be left after 4 years? | 25% will be left after two half-lives. |
What is the formula for exponential decay? | The formula for exponential decay is n = n₀e^-λt |