Question

Imagine a rock is dropped from the top of a tall building. After 2 seconds of falling, the rock’s instantaneous speed is approximately 20m/s. does anyone know is it true or false

Answer 1

True
It's in free fall( 9.8 m/s), 2 seconds have passed.

Answer 2

TRUE

Step-by-step explanation:

As we know that stone is falling freely from rest

so here we can use kinematics to find the final speed of the stone

`v_f = v_i + at`

here we know that

`v_i = 0`

`a = 9.81 m/s^2`

`t = 2 s`

now we have

`v_f = 0 + (9.81)(2)`

`v_f = 19.62 m/s`

so final speed of the rock is nearly 20 m/s