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A ball is gently dropped from a height of 20m. If its velocity increases uniformly at the rate of 10 ms-2, with what velocity will it strike the ground? After what time will it strike the ground?
By BYJU'S Exam Prep
Updated on: September 25th, 2023
A ball is gently dropped from a height of 20m. If its velocity increases uniformly at the rate of 10 ms-2, with 20 m/s velocity it will strike the ground. After 2s it will strike the ground. Steps to find the time will ball strike the ground:
Step 1: It is given that,
- Distance traveled by ball S = 20 m
- Initial velocity u = 0
- Uniform acceleration a = 10 ms-2
- Consider the time taken as t.
- Consider the final velocity as v
Step 2: Now we have to make a final velocity calculation:
Newton’s third law of motion states that:
- v2 = u2 + 2as
- v2 = 02 + 2 x 10 x 20
- v = 20 m/s
Step 3: Determine the duration using Newton’s first law of motion:
- v = u + at
- t = (v – u)/a
- t = (20 – 0)/10 = 20 m/s/ 10 m/s2
- t = 2s
As a result, the ball will hit the ground at a 20 m/s velocity at a period of 2 s.
Summary:
A ball is gently dropped from a height of 20m. If its velocity increases uniformly at the rate of 10 ms-2, with what velocity will it strike the ground? After what time will it strike the ground?
A ball is softly dropped from 20m height. It will hit the ground at 20 m/s if its velocity rises uniformly at a rate of 10 ms-2. After two seconds, it will hit the ground. Velocity is the rate of change of position with respect to time.