Mi-STAR Unit 7.1: Off-the-Grid Post Assessment

Two pine cones are falling from a pine tree.
Both are falling at the same speed (velocity).

If Pine Cone 1 weighs less than Pine Cone 2, which pine cone has more kinetic energy? 

 HINT:

 $KE=\frac{1}{2}mv^2$  

• Pine Cone 1 has more kinetic energy

• Pine Cone 2 has more kinetic energy

• Both the pine cones have the same amount of kinetic energy

• Neither Pine cone has any kinetic energy

Tags

NGSS.MS-PS3-1

A balloon with a static electric charge is placed near a student’s hair, causing the hair to stand up. Which of the following would increase the attractive force that the balloon exerts on the student’s hair?

• Changing the side of the balloon facing the hair.

• Increasing the strength of the charge on the balloon.

• increasing the size of the balloon.

• The force remains the same if the balloon is moved or the charge is changed.

Tags

NGSS.HS-PS2-4

A system you are studying contains four parts:

The Earth’s surface (the ground), a tree, Frisbee B stuck in the tree, and Frisbee A resting on the Earth’s surface

Which Frisbee has the greatest potential energy?

• Frisbee A

• Frisbee B

Tags

NGSS.MS-PS3-2

Which Frisbee has the least potential energy?

• Frisbee A

• Frisbee B

Tags

NGSS.MS-PS3-2

Frisbee B in the tree falls to the ground. As Frisbee B is falling:

• Kinetic energy of Frisbee B is increasing and potential energy is decreasing.

• Kinetic energy of Frisbee B is decreasing and potential energy is increasing.

• Both kinetic energy and potential energy of Frisbee B are increasing.

• The kinetic energy and potential energy of Frisbee B both stay the same.

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5

After Frisbee B is on the ground, someone picks up and tosses it back up in the tree.

After Frisbee B is resting on a branch again, the potential energy of the whole system increases due to .......

• the friction on Frisbee B as it is thrown.

• the force applied to Frisbee B to throw it back in the tree.

• the changes in kinetic energy as the Frisbee lands in the tree and stops.

• the transfer of energy from Frisbee B to the tree.

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-5

BRAINTEASER: Consider your answer carefully!

The kinetic energy of Object 1 is greater than the kinetic energy of Object 2.

How does the speed of Object 1 compare to the speed of Object 2?

• Object 1 is moving faster than Object 2.

• Object 1 is moving slower than Object 2.

• Object 1 is moving at the same speed as Object 2.

• The only way to know which object is moving faster is to also know the mass of each object.

Tags

NGSS.MS-PS3-1

Two magnets are at rest on a table, as shown in the diagram. In order to get the two ends of the magnets marked N to touch, which of the following is true?

• A force must be applied since the two ends marked N repel each other.

• A force must be applied since the two ends marked N attract each other.

• The magnets will touch without any force being added.

• The magnets can only be made to touch if one of the magnets is reversed.

Tags

NGSS.MS-PS2-5

Which of the following statements about electric and magnetic forces is TRUE?

• Both electric and magnetic forces can be attractive.

• Magnetic forces can be repulsive, but electric forces cannot.

• Electric forces are not affected by distance, but magnetic forces are.

• Magnetic and electric forces do not interact.

Tags

NGSS.MS-PS2-3

Two strong magnets are attracted to each other and are touching, as shown in the diagram. You pull them apart. What will happen to the force the magnets exert on each other as they move apart?

• As the magnets begin to move apart, they immediately stop exerting a force on each other.

• As the magnets begin to move apart, the force exerted between the magnets increases.

• As the magnets begin to move apart, the force exerted between the magnets decreases.

• As the magnets begin to move apart, no change in force occurs.

Tags

NGSS.MS-PS2-5