Question

A ball is thrown at an angle of 38° to the horizontal. What happens to the

magnitude of the ball's vertical acceleration during the total time interval that

the ball is in the air?

O It decreases, then increases.

O It remains the same.

O It decreases, then remains the same.

•It increases, then decreases.

Answer 1

Vy = V0 sin 38 where Vy is the initial vertical velocity

The ball will accelerate downwards (until it lands)

Note the signs involved if Vy is positive then g must be negative

The acceleration is constant until the ball lands

t (upwards) = (0 - Vy) / -g = Vy / g final velocity = 0

t(downwards = (-Vy - 0) / -g = Vy / g final velocity = -Vy

time upwards = time downwards (conservation laws)