P6 Energy and Forces

A man drives a car up a slope. He applies the brakes to stop the car along the slope. The energy of the moving car is changed into ____________________.

• heat energy only

• kinetic energy only

• heat energy and potential energy

• kinetic energy and potential energy

Jeremy rode a skateboard down a ramp as shown in the diagram.

Which of the following descries the changes in potential and kinetic energy from A to B?

• Potential energy - decreases

  Kinetic energy - decreases

• Potential energy - decreases

  Kinetic energy - increases

• Potential energy - increases

  Kinetic energy - increases

• Potential energy - increases

  Kinetic energy - decreases

Ta Wen stood on a swing and moved to and fro through a height as shown in the diagram below.

Which one of the following graphs correctly shows how the potential energy and kinetic energy of the swing change with the height?

• 
• 
• 
• 

Jenny kicked a ball from A to B as shown.

Which one of the following statements is NOT correct?

• The mass of the ball remained the same.

• The force exerted by Jenny moved the ball.

• The potential energy of the ball increased from A to B.

• The gravitational force acting on the ball increased from A to B.

John held a toy between his hands as shown. He rotated the toy by sliding his right hand forward and his left hand backwards before releasing it. The toy flew to a certain height after it left his hands.

He rotated the toy at the same starting position again. But this time, the toy flew to a lower height than it did before.

Which one of the following could explain why the toy flew to a lower height?

• The weight of the toy was greater.

• The heat gained by the toy was smaller.

• The kinetic energy of the toy was smaller.

• The gravitational potential energy of the toy was greater.

A toy car was pushed towards a wooden plant AB as shown in the diagram. It moved up the plank, stopped at X and then it rolled down the plank.

Which one of the following statements about the movement of the car is true?

• The car rolled down because of gravitational force.

• The car stopped at X because it had lost all its potential energy.

• The car stopped at X because there were no forces acting on it.

• The car slowed down as it moved up because frictional force increased.

The diagram shows a round glass bowl. A metal ball was held at P. When the ball was released, it rolled down.

Which one of the following statements is the most likely path of the ball after it was released?

The ball rolled to ________________________.

• Q and then rolled back

• R and then rolled back

• S and then rolled back

• S and out of the bowl

A force was applied to move a wooden block.

Which one of the following correctly shows the direction of motion and direction of friction acting on the wooden block?

• 
• 
• 
• 

Hassan conducted an experiment using the set-up below.

Hassan released the cube and measured the distance moved.

He repeated the experiment by using two similar rubber bands instead of one. He released the cube from the same position and measured the distance moved.

Which of the following would happen when two rubber bands were used?

• The cube did not move.

• The cube moved a longer distance.

• The cube moved a shorter distance.

• The cube moved the same distance.

A man wanted to move a box down a slope. He gave a push to the box at G, but the box only reached point H.

Which one of the following statements is not correct for the movement of the box down the slope?

• The box slowed down because of frictional force.

• Frictional force was acting upwards along the slope.

• The box stopped at H because there was no force acting on it.

• Gravitational force acting on the box remained the same from G to H.