Question

A rock is thrown downward from the top of a cliff with an initial speed of -13m/s.If the rock hits the ground after 2.7 s, what is the height of the cliff

Answer 1

0.62 m down.

Step-by-step explanation:

Use the formula d= vi*t +1/2 at^2

So the initial speed or vi is -13 m/s and time is 2.7 s and a or acceleration is 9.8 m/s^2 down ( because it's the gravity). So you plugged all the values and you will get 0.62 m. We put the down because the acceleration is saying down. Because displacement is vector quantity you have to show the direction of it.