Question

A pillow is thrown downward with an initial speed of 6 m/s.

Answer 1

Given :

Initial velocity, u = -6 m/s.

Time taken, t = 4 seconds.

Acceleration due to gravity, $g = -9.8\ m/s^2$.( Here negative sign means downward direction )

To Find :

Velocity after 4 seconds.

Solution :

By equation of motion.

v = u + at

Here , a = g.

v = u + gt

v = -6 + (-9.8)×4

v = -6 + (-39.2)

v = -45.2 m/s

Therefore, velocity after 4 seconds is -45.2 m/s.

Hence, this is the required solution.