7.P.2.1,2,3,4 Review

This graphic shows the motion of a pendulum. The pendulum is released from rest at position 1, and then swings through positions 2-5. What is the pendulum’s mechanical energy at position 1?

• potential energy = 100%; kinetic energy = 0%

• potential energy = 25%; kinetic energy = 75%

• potential energy = 50%; kinetic energy = 50%

• potential energy = 75%; kinetic energy = 25%

The diagram below shows a man using a lever to move a rock.

Which change can he make to the fulcrum to decrease the force he has to apply?

• remove the fulcrum

• put the fulcrum on top of the lever

• move the fulcrum closer to himself

• move the fulcrum closer to the rock

Which statement best explains how inclined planes create mechanical advantage and affect efficiency?

• Inclined planes reduce the amount of force necessary to move an object a specified height over a distance, increasing efficiency.

• Inclined planes reduce the amount of force necessary to move an object a specified height over a distance, decreasing efficiency.

• Inclined planes increase the amount of force necessary to move an object a specified height over a distance, increasing efficiency.

• Inclined planes increase the amount of force necessary to move an object a specified height over a distance, decreasing efficiency.

Adam had a string of lights. The whole string of lights stopped glowing when one of the lightbulbs burned out.

What caused this to happen?

• The burned-out lightbulb opened the circuit.

• The burned-out lightbulb closed the circuit.

• The burned-out lightbulb drained the power source.

• The burned-out lightbulb caused a surge in the power source.

This is a diagram of four simple machines.

Which simple machine would most likely be used to move an object over great distances and on a flat surface?

• R

• S

• T

• U

Which of the following is used as a wedge?

• baseball bat

• a bicycle handle

• a faucet handle

• a sewing needle

Which yard tool has a wheel and axle that helps move a pile of dirt?

• 
• 
• 
• 

Which is the best example of a first-class lever?

• 
• 
• 
• 

How does using a pulley to lift an object increase mechanical advantage?

• by decreasing the mass of the object being lifted

• by increasing the mass of the object being lifted

• by increasing the amount of force needed to lift the object

• by decreasing the amount of force needed to lift the object

In which part of an electric circuit does energy originate?

• battery

• bulb

• switch

• wire