projectile motion

If a ball thrown straight up into the air takes 4 seconds to reach the top (peak), how long will it take to travel from the peak back to the original position?

• 0s

• 1s

• 3s

• 4s

The fact that an apple and a watermelon, dropped simultaneously from the same height, would hit the ground at the same time indicates that

• you don't like apples or watermelons.

• greater masses have greater acceleration.

• lesser masses have greater acceleration.

• acceleration is independent of mass.

The initial horizontal velocity of a projectile is ____ its final horizontal velocity.

• less than

• equal to

• greater than

What is true about the vertical velocity of a projectile launched horizontally?

• It is initially at its maximum value.

• It increases due to gravity as it falls.

• It remains constant throughout its trajectory.

• It decreases as it falls due to gravity.

If two projectiles are launched at two different heights, 2m and 10m, which one will reach the ground first?

• 2m

• 10m

• they both will hit the ground at the same time

Which hits the ground first if they start at the same height: a dropped ball or a ball launched with a

horizontal velocity?

• the launched ball

• the dropped ball

• they both hit at the same time

An airplane traveling at constant velocity drops a bomb. Where is the airplane when the bomb hits the

ground?

• above the bomb

• before the bomb

• past the bomb

What is the velocity of an object launched straight up at its highest point?

• zero

• equal to its v_x

• ½ its maximum value

• equal to gravity

Once a projectile is launched, what is the only force that affects its motion?

• mass

• friction

• inertia

• gravity

If you throw a baseball straight up, what is its acceleration at the highest point?

• 9.8 m/s²
• 9.8 m/s
• 0 m/s²
• 0 m/s