Midterm

Adding energy to a substance makes its particle move..

• slower

• fast

• does nothing

• same speed

Answer explanation

If you remove energy, the particle will move slower, if you add energy it'll move faster!

Two objects get closer.. The gravitational force between them..

• Increases

• decreases

• remains the same

• nothing happens

Answer explanation

As objects get closer, the gravitational force gets stronger!! the farther they are, the weaker the gravitational force!

There are two points. Each has a negative charge. They will each

• attract each other

• nothing will happen between them

• Repel each other

Answer explanation

Opposites attract! negative charges and positive charges will attract each other. Negative charge and another negative charge will repel. Same with 2 positive charges

On earth, there is an apple hanging from a tree. Which statement is true?

• Gravitational Force exerted by the apple is less because it's less mass

• Gravitational Force exerted by earth is less because it's far from the apple

• Gravitational Force exerted by the apple is more because it's hanging

• Gravitational Force exerted by the apple and earth are equal

Answer explanation

They are equal because it's balanced! if the apple was falling then it would gain acceleration down.. Not balanced!

Box 1: 10 kg

Box 2: 20 kg

Box 3: 30 kg

Box 4: 40 kg

If one of these boxes were thrown, which one would have the greatest momentum?

• Box 1: 10 kg

• Box 2: 20 kg

• Box 3: 30 kg

• Box 4: 40 kg

Answer explanation

Box 4 is the heaviest of all the boxes, which would have a greater impact when thrown. It would have the greatest momentum.

The force of attraction between two masses is ____ proportional.

Acceleration = Change in velocity/time = ​ (a)   -​ (b)   / time

• final velocity
• initial velocity
• last velocity
• middle velocity

The force of attraction between is ____ proportional to the square of the distance between their centers.

Match the following units

• m

• N

• F

• kg

• a

• m/s²

​ (a)   is a lot like speed except for one important difference, it’s a vector which means it has a direction attached to it.

• velocity
• acceleration
• constant
• force