Energy, Work and Simple Machines Study Guide

  1. What is the difference between potential energy and kinetic energy
  1. As the velocity of a runner increases, which type of energy also increases?
  1. A roller coaster is climbing up the highest hill on its track. At which point will the front car of the coaster most likely have its greatest potential energy?
  1. What is the kinetic energy of a 0.500 kg toy car moving at a rate of 1.50 m/s
  1. The sound made by crickets occurs when the male crickets rubs its two hind legs together. Which type of energy transformation results in the sound made by crickets?
  1. An electric bulb will stop shining when a light switch is shut off because
  1. What form of energy is stored in a battery?
  1. A simple machine that has a mechanical advantage equal to 1 would most likely be used to
  1. Which simple machine uses a fulcrum to redirect a force?
  1. Tomas wants to paint his bedroom. He goes to the store and buys two cans of paint.
Which simple machine would make it easier for him to open the cans?
  1. The input and output forces for four machines are shown in the table.
Machine Forces
Machine / Input Force
(N) / Output Force
(N)
1 / 5 / 50
2 / 10 / 50
3 / 25 / 50
4 / 50 / 50
Which machine would have the greatest mechanical advantage?
  1. Which simple machine increases the distance over which a load travels and reduces the needed force?
  1. Joshua lifted a 100-newton (N) box by doing 120 joules (J) of work. How high did he lift the box?
  1. A log splitting machine was invented to split logs quickly. A motor powers a metal piece that is pushed through the middle of a log.The metal piece used to split a log is an example of what simple machine?
  1. Mr. Moyers’ class was studying how work is done on an object. In which situation is the amount of work done on the object equal to zero?
A.A shopper pushes a cart with a broken wheel.
B.An apple growing on a tree falls to the ground.
C.A person pushes on a heavy box but is unable to move it.
D.An athlete swings a bat in the air without hitting anything.
  1. A wheelbarrow is a compound machine that uses simple machines to change the direction or size of a force.Which simple machines are used to form this compound machine?
  2. A 1200-newton box is placed in a delivery truck 1.0 meter high. A worker used a 400 newton force to push the box up a 4-meter inclined plane. What is the efficiency of the inclined plane?

  1. Which machine could be considered to be a type of inclined plane?

A. / wheel and axle
B. / lever
C. / Screw
D. / pulley
  1. A student applied a force of 200 N to push a box 15 m down the sidewalk. Given the formula, W = F × d, how much work has been done?
  2. An electric can opener uses a magnet to hold a can in place. As the wheel on the can opener turns, a blade cuts the top of the can open.The blade on the can opener is an example of what kind of simple machine?

  1. Movers needed to move a heavy box from the bottom of some stairs to the top of the stairs. They placed a ramp over the stairs and pushed the box up the ramp.
    Which best explains why the movers used a ramp to move the box?

A. / The ramp reduced the amount of force needed to move the box.
B. / The ramp increased the height that the box needed to be moved.
C. / The ramp reduced the distance that the box needed to be moved.
D. / The ramp increased the amount of friction needed to move the box.
22. / Two different types of pulleys are shown. Pulley 1 is a fixed pulley and Pulley 2 is a movable pulley.What is Pulley 2 designed to do that Pulley 1 cannot do?
  1. The table below shows different situations involving a box.

Situation
1 / A box is lifted 6 meters in the air by a forklift.
2 / A box is lifted 3 meters off the ground by a person.
3 / A box is lifted 10 meters in the air by a crane.
4 / A box is left on the ground by a student.

List the situations organized from least to greatest amount of work done on the box?

  1. The table shows forces applied to four carts with wheels and the distance each cart traveled.

Cart / Force (N) / Mass (g) / Distance Traveled (m)
W / 4 / 125 / 2.5
X / 4 / 125 / 2.0
Y / 6 / 125 / 1.0
Z / 6 / 125 / 1.5

In which scenario was the most work done?

  1. Which best represents the use of mechanical energy?

A. / a light bulb giving off heat
B. / a candle providing light
C. / a nail being hammered
D. / a can rusting
  1. A rock that falls off a cliff demonstrates both potential and kinetic energy.

Which is the best comparison of these two forms of energy?
A. / As the kinetic energy increases, the potential energy decreases.
B. / As the potential energy decreases, the kinetic energy decreases.
C. / The amount of kinetic energy is equal to one-half of the potential energy.
D. / The amount of potential energy is equal to one-fourth of the kinetic energy.
27. / The drawing shows a waterfall flowing into a pool of water.

Which statement best describes the energy of the objects in the drawing?
A. / The pool of water has morekinetic energy and the falling water has more potential energy.
B. / The falling water has potential energy and the rock over which it flows has kinetic energy.
C. / The water has potential energy at the top of the waterfall andincreasing kinetic energy as it falls.
D. / The water at the top of the fallhas kinetic energy that becomes potential energy as it falls into the pool.
28. / Mrs. Pearson’s class is studying the amount of energy stored in objects. If the same rock is put in four different places, at which location will the rock have the most potential energy?
A. /
B. /
C. /
D. /
29. / The line shows the path of the ball.

As the ball moves from Point 3 to Point 4, which energy conversion is taking place?
30. / A log splitting machine was invented to split logs quickly. A motor powers a metal piece that is pushed through the middle of a log.

The metal piece used to split a log is an example of what simple machine?
31. Which conditions indicate that work was not done?
32. / Four identical cans are arranged on the shelves of the bookcase shown.

Which can has the greatest potential energy?
33. / During an investigation on energy, Seth rolls marbles of four different masses down a ramp.

Which size marble will have the greatest kinetic energy when it reaches the bottom of the ramp?
34. / Refer to the electric circuit to answer the question that follows.

Light bulb 2 burned out in this circuit. If voltage remains constant, what happens to the remaining light bulbs?
35. / A student is investigating the transfer of electrical energy in a circuit. In which circuit will electrical energy light the bulb?
A. /
B. /
C. /
D. /
36. / What is the function of the wire in the diagram below?

37. / In which circuit will the light(s) be on?
A. /
B. /
C. /
D. /
38. / The diagrams show forces applied to an object.

Which diagram shows the most work being done?
39. / Seth wanted to remove a large rock from his garden.

Which tool would make it easiest to lift the rock out of the soil?
A. /
B. /
C. /
D. /
40. / Which simple machine uses a fulcrum to redirect a force?
A. /
B. /
C. /
D. /
41. / A student uses the fulcrum and board shown below to move a large rock. The student’s friends suggest ways to revise the design.

Which suggestion best helps the student move the rock while using less force?
A. / put the fulcrum on top of the board
B. / move the fulcrum closer to the rock
C. / apply force directly above the fulcrum
D. / completely remove the fulcrum
42. / Workers push a heavy box up an inclined plane and onto a truck.

Which best explains why these workersuse aninclined plane?
A. / It makes their work easier.
B. / It keeps their clothing clean.
C. / It keeps the box from breaking.
D. / It makes the box weigh less.
42. / The box labeled X rests on a lever. A force, represented by the arrow, is needed to lift the box.

What is another name for the box?
A. / effort arm
B. / resistance arm
C. / effort force
D. / resistance force
43. / Leticia is trying to lift a box using the least amount of force. Which first-class lever should she use?
A. /
B. /
C. /
D. /