Motion

Which of the following is a vector quantity?

• Speed

• Distance

• Displacement

• Time

The S.I. unit for acceleration is:

• m/s

• m/s²

• m²/s

• kg/m²

Which of the following equations is NOT used to calculate the final velocity of an object under constant acceleration and different from zero?

• v=u+at

• a = (v-u)/t

• v² =u²+2as

• s=ut

A body is in free fall. Its acceleration is:

• 9.8 m/s² downward

• 9.8 m/s² upward

• 0 m/s²

• 4.9 m/s² downward

True or False: The horizontal component of a projectile’s velocity changes during flight.

• True

• False

Which of the following best represents a scalar quantity?

• Velocity

• Displacement

• Distance

• Acceleration

If a ball is thrown straight up into the air, at the highest point, the velocity of the ball is:

• Maximum

• Minimum

• Zero

• Equal to the initial velocity

A projectile is launched at an angle of 30° with a speed of 20 m/s. The horizontal component of the initial velocity is:

• 20 m/s

• 10 m/s

• 17.32 m/s

• 14.64 m/s

Which of the following statements about free-falling bodies is correct?

• Mass affects the rate of fall.

• All objects fall at the same rate in a vacuum.

• Heavier objects fall faster than lighter ones in the air.

• Air resistance increases acceleration.

True or False: In the absence of air resistance, all objects fall with the same constant acceleration.

• True

• False