Question

An object is dropped from rest.

What is its instantaneous speed when it has
been in motion for 3 s? The acceleration of
gravity is 9.8 m/s
2
.
Answer in units of m/s.

Answer 1

29.4m/s

Step-by-step explanation:

Given parameters:

Duration of motion = 3s

Acceleration due to gravity = 9.8m/s²

Unknown:

Instantaneous speed = ?

Solution:

Instantaneous speed is the speed at an instant or a particular time.

Since initial speed = 0 because it was at rest, the best motion equation to solve this problem is given as;

V = U + gt

Where V is the instantaneous speed

U is the initial speed

g is the acceleration due to gravity

t is the time taken

Insert the parameters and solve;

V = 0 + 9.8 x 3 = 29.4m/s