Free Fall

A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball when caught would be 

• less than the speed it had when thrown upwards.

• more than the speed it had when thrown upwards.

• the same as the speed it had when thrown upwards.

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-1

NGSS.MS-PS3-5

Free fall is any motion of a body where ____ is the only force acting upon it.

• body attraction

• tension

• gravity

• velocity

Tags

NGSS.MS-PS2-4

Two rocks with different size and mass are dropped from the same height. Which of the rock will reach the ground first?

• greater rock

• smaller rock

• both reach the ground at the same time

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

In a normal environment, why does a bowling ball and feather hit the ground at different times when dropped from the same height?

• They don't; they hit the ground at the same time.

• One is more dense than the other.

• One is heavier than the other.

• Air resistance 

If an object is in free fall for three seconds, how fast will it be falling at the end of its motion?

• 9.8 m/s

• 19.6 m/s

• 29.4 m/s

• 39.2 m/s

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-1

A textbook is dropped from a second floor window and falls to the ground. What happens to the velocity as the book falls to the ground?

• the velocity increases

• the velocity decreases

• the velocity remain constant

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

NGSS.MS-PS3-1

NGSS.MS-PS3-5

A rock from a volcanic eruption is launched straight up into the air with no appreciable air resistance. Which one of the following statements about this rock while it is in the air is correct?

• On the way up, its velocity is upward, and at the highest point its velocity is zero.

• On the way down, its velocity is downward, and at the highest point its acceleration is zero.

• Throughout the motion, the velocity is always in the same direction as the acceleration.

• The acceleration is downward at all point in the motion except that is zero at the highest point.

Tags

NGSS.MS-PS2-4

A construction worker accidentally drops a brick from a high scaffold. What is the velocity of the brick after 4.0 s? Assume that downward is negative.

• +39 m/s

• -39 m/s

• +2.45 m/s

• -2.45 m/s

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

Acceleration due to gravity is equal to...

• 4.91 m/s²

• 8.76 m/s²

• 9.81 m/s²

• 19.62 m/s²

Tags

NGSS.MS-PS2-4

When an object is thrown in the air, what is its velocity at the max height?

• -9.81 m/s

• 0 m/s

• 9.81 m/s

• 10 m/s