Question

A stone drop from cliff calculate is speed after if fall in 80 cm G (10ms²)​

Answer 1

Given Information :

• A stone drop from cliff.
• It fall in 80 cm (G = 10ms²).

To Calculate:

• The speed.

Solution:

Using 2nd equation of motion,

v = ut + 1/2 at²

h = ut + 1/2 gt²

0.8 = 0 + 1/2 × 10t²

0.8 = 5t²

5t² = 0.8

t² = 0.8/5

t = 2/5

t = 0.4second

Using 1st equation of motion,

v = u + at

v = u + gt

v = 0 + 10 × 0.4

v = 4m/s (Required Answer)