Question

Objects fall near the surface of the earth with a constant downward acceleration of 10 m/s2 . At a certain instant an object is moving upward at 20 m/s. What is its velocity 2 sec later?

Answer 1

Answer:

After 2 seconds the velocity of the object is 0 m/s.

Explanation:

The velocity at 2 seconds later can be calculated as follows:

$V_{f} = V_{0} - gt$

Where:

$V_{f}$: is the velocity at 2 seconds

$V_{0}$: is the initial velocity = 20 m/s

g: is the gravity = 10 m/s²

t: is the time = 2 s

Hence, the final velocity is:

$V_{f} = V_{0} - gt = 20 m/s - 10 m/s^{2}*2 s = 0 m/s$

This value (0 m/s) means that the object has reached the maximum height.

Therefore, after 2 seconds the velocity of the object is 0 m/s.

I hope it helps you!