Big Ideas

Bar magnets have a north pole (N) and a south pole (S). Latrisha places a bar magnet on three small straws so that it can roll. Her setup is shown below.

Placing which of the following objects at point X will cause the bar magnet to move away from point X?

• an iron nail

• an aluminum can

• the north end of another bar magnet

• the south end of another bar magnet

Tags

NGSS.3-PS2-3

Stephanie started pushing a bookcase across the room, as shown in picture 1. Then, she removed the books and continued pushing with the same force and direction, as shown in picture 2.

How does removing the books affect the motion of the bookcase?

• The mass is decreased, making the bookcase move faster

• The gravity is increased, making the bookcase move slower

• The friction is increased, making the bookcase move slower

• The mechanical energy is decreased, making the bookcase move faster

Tags

NGSS.MS-PS2-2

Rebecca kicks a ball with a certain force. Then Leo kicks the same ball with a larger force.

Which of the following will most likely happen?

• the ball will move faster and farther when Rebecca kicks it

• the ball will move more slowly and farther when Rebecca kicks it

• the ball will move faster and farther when Leo kicks it

• the ball will move faster and not as far when Leo kicks it

Tags

NGSS.MS-PS2-2

A student starts a ball rolling down a hill. The ball rolls faster as it goes down the hill, even though no one is pushing it any more.

Why does the ball move faster?

• The ball is losing energy, so it moves faster.

• The initial force is still at work, so the ball moves faster.

• The ball creates its own energy, so the ball moves faster.

• Another force is acting on the ball, so the ball moves faster.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-1

NGSS.MS-PS3-5

Ellen is investigating the flow of electricity through circuits. She sets up a circuits as shown and observes that the light bulb remains unlit.

What can Ellen do differently to change the results of her experiment and why?

• She can use a bigger battery because it will provide more power.

• She can move the light closer to the battery because it will increase the power.

• She can open the switch because it is blocking the flow of electricity near the battery.

• She can connect the wire on the switch to the battery so that they electricity can flow through the entire circuit.