Steel is a good example of a(n) because its material allow heat to pass through it. *

1 point

machine

conductor

mechanical advantage

insulator
15. a man relaxes in his hot tub after a long day at work. his body temperature is 98.6°f. the temperature of the water in the hot tub is 104°f. how does heat transfer? *

1 point

heat transfers from his body to the water by convection.

heat transfers to his body from the water by conduction.

heat transfers from his body to the water by conduction.

heat does not transfer between his body and the water.
16. is a good example of an insulator because it is a material that does not easily allow the passage of heat or sound. *

1 point

wood

silver

metal

copper
17. during a skydiving landing, a parachute deploys from the back of the diver as it taxis back down to the earth. the parachute the diver slow down before landing. how does the parachute during this process? *

1 point

it increases the weight of the shuttle.

it increases the potential energy of the shuttle.

it increases heat transfer by radiation.

it increases friction by air resistance.
18. a construction worker is using his weight to keep a stationary stack of wooden beams from falling. if the construction worker uses 738.0 n of force to hold 15 beams stationary against a wall, how much work does he do? *

1 point

0 j

0.260 j

73.9 j

7380.0 j
19. calculate the efficiency of a bicycle if the input work to turn the pedal is 45j and the output work is 20j. *

1 point

2.25

2.25%

44

44.4%

other:

20. if the input force of moving a box up a ramp is 10n and the output force is 30n, what is the mechanical advantage? *

1 point

3

30

.33

300
21. you lift a cat with a force of 40 n up to a table that is 0.5 m high. how much work did you do? *

1 point

80j

40j

20j

10j
22. what is always the direction of heat transfer? *

1 point

from the colder object to the warmer object

heat energy does not transfer

from the warmer object to the colder object
23. a field force, or a non-contact force, is a force that pushes or pulls an object without direct contact; instead, it acts at a distance. which of the following are examples of field forces? *

2 points

pushing a swing
gravity
pulling a weed out of the soil
magnetism
example 1

example 2

example 1
example 2
24. what form of potential energy occurs at point c that allows the pole vaulter to lunge up into the air? *

1 point

gravitational potential energy

chemical potential energy

magnetic potential energy

elastic potential energy
25. at which position will the bar magnets most likely experience the most magnetic potential energy between them? *

1 point

position 1

position 2

position 3

position 4
26. just as with gravitational potential energy, it requires work from an outside force to move an electrically charged object against its natural direction. this will the object’s electric potential energy. *

1 point

decrease

increase

triple

cause no change to
27. which of the following scenarios would cause a decrease in magnetic potential energy? *

2 points

a north and a south pole attracting
forcing two north poles together
two south poles repelling
pulling a north and a south pole apart
scenario 1

scenario 2

scenario 1
scenario 2
28. at which point in the following image does the trampoline have the least elastic potential energy? *

1 point

1

2

3
29. which of the following is an example of nuclear potential energy? *

1 point

a sandwich

a match

the sun

a magnet
30. the type of energy associated with motion, position, or shape of an object is called *

1 point

electromagnetic energy

nuclear energy

thermal energy

mechanical energy
31. matches have what form of potential energy? *

1 point

chemical

magnetic

elastic

gravitational
32. rahul conducted an experiment with three bags containing similar wooden cubes. bag a contains 4 cubes, bag b contains 2 cubes, and bag c contains 6 cubes. rahul dropped all three bags at the same time from the same height of 2 meters. which one of the following is correct? *

1 point

bag b has less kinetic energy than bag a at the same level as it falls.

bag c has the most kinetic energy before it was released.

bag a has more kinetic energy than bag c at the same level as it falls.

bag a has the least gravitational potential energy when it was released.