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Fraser Study Guide 2
Fraser - 2
Question | Answer |
---|---|
If an object changes its direction of motion, then... | A force must have been applied to the object. |
The inertia of an object comes from its: | mass |
If no forces are acting on an object, its motion will: | continue in the same direction with the same speed |
What action must be taken to change the motion of an object? | Force must be applied to the object. |
An ice skater feels very little force as she moves in a straight line on her skates. According to Newton's first law, which of the following statements about her motion is true? | She must apply force with her skates to turn or stop. |
Two objects have the same inertia if: | the same force causes the same acceleration in both objects |
Which of the following situations can NEVER happen because it represents a violation of Newton's first law? | The speed of an object changes even though no forces are acting on the object |
The acceleration of an object is: | equal to the force acting on the object divided by the mass of the object |
3 forces are acting on an object. The object is not moving. 2 forces are 2 newtons and 10 newtons, what is the third force? | 12 Newtons |
An object is observed to have an acceleration of 2m/s2 when a net force of 4 newtons is applied. The mass of the object is? | 2.0 Kilograms |
Which of the following best describes Newton's second law? | Mass is a measure of an object's resistance to acceleration. |
Force is best defined as: | any action that could change the motion of the object. |
The newton is a unit of force that is defined by: | the acceleration of 1 m/s2 of an object with a mass of 1 kilogram |
The units of force come from Newton's second law (F=MA). In the metric system, the units for force are: | kg x m/s2 |
A boy on a skateboard throws a ball. The skateboard moves in the opposite direction from the thrown ball because: | the ball exerts a reaction force on the boy as it is being thrown |
Which of the following is NOT TRUE about an action-reaction force pair of forces? | the action force is applied first and the reaction force appears later |
A 0.25-kilogram ball is observed to accelerate at 4,000 m/s2 as it is hit with a bat. How much force is exerted on the bat by the ball? | 1,000 Newtons |
The weight of 1-kg mass is: | 9.8 newtons |
The force called weight comes from: | gravity |
A bunch ob bananas weights 1.5 lbs on the scale at the grocery store. The mass of the bananas is: | 0.68 kilograms |
A force of 10 lbs is applied to a wagon that weights 100 lbs. The acceleration of the wagon is closest to: | 1 m/s2 |
A person who weights 150 lbs (672 N) when standing still. He observes that he weighs 225 lbs (1,008 N) on an elevator moving upward. What is the acceleration of the elevator? | 4.9 m/s2 |
Viscous friction occurs when: | wet surfaces slide over each other |
The coefficient of static friction is: | larger than the coefficient of sliding friction |
A force of 5 N is required to slide a block at constant speed over the dry surface of a table. The block has a mass of 2.5 kg. The coefficient of sliding friction is: | 0.2 |
An aircraft accelerates at 49 m/s2. Express the acceleration in multiples of acceleration of gravity (g). | 5 g's |
According to Hooke's law: | an object resists being stretched with a force equal to the spring constant multiplied by the change in length by which the object is stretched |
A machine for lifting heavy equipment uses a steel cable. The equipment is supported by 6 strands of cable. The equipment being lifted has a mass of 1,500 kg. What is the force in EACH of the six supporting cables? | 2,450 newtons |
An example of a simple machine is: | a bicycle wheel, a pair of scissors, a knife. (all of the above) |
People who design technology are called: | engineers |
The mechanical advantage of a machine may be calculated as the ratio of: | input distance to output distance |
A weight of 250 newtons is placed 2 meters from the fulcrum of a lever. If an input force of 50 newtons is used to lift the weight, the force must be applied ______ from the fulcrum. | 10 Meters |
The joule is a derived unit or a combination of: | newtons and meters |
Of the following examples, the one that represents work as defined by a scientist is: | lifting a book from your desk |
A 9,000-newton elephant is lifted 2.0-meter using a 100-newton force. What is the work output, expressed in newton-meters? | 18,000 |
If the motor winds the elevator's cable at 4 feet per second, how long will it take to raise the elevator 20 feet? | 30 seconds |
The ability to do work is defined as: | energy and measured in joules |
A 2,000-kilogram automobile accelerates horizontally to a speed of 20 m/s. Tee increase in its gravitational potential energy is: | 0 joule |
The kinetic energy of a go-cart with a mass of 10 kilograms and a speed of 20.0 m/s is: | 30,000 joules |
A 20-gram arrow is given a potential energy of 65 joules as the bowstring is drawn back into position. As the arrow leaves the bow, its speed is about: | 68 m/s |
The wavelength of a wave can best be determined by measuring the distance between: | one crest and the next one |
A wave is: | an oscillation that travels from one place to another |
The speed of a water wave describes the speed at which: | the wave's oscillations spread from one place to another |
The oscillations of a transverse wave are: | perpendicular to the direction of the wave's motion |
The speed of a wave is equal to: | the wavelength multiplied by the frequency |
A student observes a water wave in a tank of water. Which of the following techniques is NOT an acceptable way to measure the frequency of a wave? | Count how many waves it takes to stretch from one side of the tank to the other. Divide by the number of waves by the width of the tank. |
Constructive interference occurs when two waves: | add up to create a wave that is LARGER than either single wave |
The process by which the amplitude of a wave is slowly reduced as the wave loses energy while moving through a substance is called: | absorption |
A plane wave is a wave: | with crests in the shape of lines |
Diffraction causes waves to: | spread out through small openings |
The direction a wave moves is: | perpendicular to the wave fronts |
When two waves interfere with each other, the word interfere means? | the motion we observe is the sum of the motions from each individual wave |
Which of the following is NOT possible when two waves interfere to create a third wave? | The new wave can be identical to one of the single waves |
Resonance in standing waves is caused by: | interference with reflections from boundaries |
A node is best described as: | a place where the amplitude of motion is smallest |
The energy stored in a standing wave INCREASES when: | the frequency increases, and the amplitude stays the same |
The natural frequency of a vibrating string stretched between two fixed boundaries is: | the wave's speed divided by twice the string's length |
Inertia is a property of matter that resists ______. | acceleration |
The difference between pounds and kilograms is that _____ are a unit of force while _______ are a unit of mass. | Pounds, kilograms |
Objects usually require more force to get started than to keep moving because ______ _______(two words) is greater than kinetic friction. | Static Motion |
When the net force on an object is zero, the object is in _________. | Equilibrium |
The ______ _______(two words) in Hooke's law describes how much force it takes to stretch an object by one unit of length. | Spring Constant |
The process of design, prototype, test, and evaluate is called the __________ _______.(two words) | Engineering Cycle |
If the output gear turns more than the input gear, it will turn with ______ force and _____ speed. | less, more |
The work _____ of a simple machine can never exceed the work _____. | output, input |
A pulley system is used so that a 50-newton force can lift a 350-newton weight. The minimum number of ropes in a pulley system that must support the weight is _____. | Seven (7) |
The ability to do work or create a force is called ______. | energy |
A point on a standing wave where the amplitude is greatest is called an _________. | Antinode |
When two waves add up to a wave that is smaller than the original waves, the process is called ________ interference. | destructive |
A unit of force able to accelerate a 1-kilogram object at m/s2 | Newton |
The condition where the net force is zero | Equilibrium |
When this is zero, an object maintains its motion at a constant speed and direction. | Net Force |
The action that can change motion | force |
A property of matter that creates inertia | mass |
A metric unit that can be used for weight | Newton |
A unit of mass | kilogram |
The physical process that give objects their weight | gravity |
A situation with zero net force | equilibrium |
The force acting perpendicular to a surface | normal force |
The fore acting perpendicular to a surface | normal force |
Friction between two surfaces that are not moving relative to each other | static friction |
A situation when zero net force | equilibrium |
A rule relating the force and change in length of an object | Hooke's Law |
A force that happens when we surfaces slide over each other | viscous friction |
Force a machine applies on an object to be moved | output force |
Device that makes doing work easier | machine |
Force you apply to a machine | input force |
A complex machine made of two or more simple machines | mechanical system |
Ratio of output force to input force | mechanical advantage |
Type of energy a moving car contains | kinetic energy |
An example of this occurs when you strike a match and it emits heat and light. | transformation of energy |
Tends to waste energy by converting it to heat | friction |
Exemplified by the rule "work input equals work output" | conservation of energy |
Type of energy contained by a stretched spring or a ball at the top of a hill | potential energy |
The number of cycles per second completed by an point on a wave | frequency |
The distance between two successive crests of a wave | wavelength |
A wave with oscillations perpendicular to the direction the wave moves | transverse |
A property of a wave that is frequency multiplied by wavelength | speed |
Waves that spread radially outward from a single point | circular waves |
What happens when two or more waves are in the place | interference |
The process by which a wave spreads out through small openings | diffraction |
A property of a wave that increases with amplitude and frequency | energy |
An interaction between a periodic force and a standing wave | resonance |
Resonances that are multiples of the fundamental frequency | harmonics |