Question

A body is moving vertically upwards. Its velocity changes at a constant rate from 50 m/s to 20 m/s in 3 s . What is its acceleration ?

February 16, 2024

Answer

Initial velocity (u) = 50 m s ^-1

Final velocity (v) = 20 m s ^-1

Time (t) = 3 s

Acceleration (a) = $v-u\over t$

= $20-50\over 3$

= $-30\over 3$ = -10 m s^-2

Hence, the acceleration of the body is -10 m s ^-2. A negative sign shows that the velocity decreases with time, so retardation is 10 m s^-2.

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