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A ball A is dropped from a building of ...

A ball ` A` is dropped from a building of height ` 45 m`. Simultaneously another ball ` B` is thrown up with a speed ` 40 m//s`. Calculate the relative speed of the balls as a function of time.

Text Solution

Verified by Experts

For the ball dropped from the building, `u_(1) = 0, u_(2) = 40 m//s`
Velocity of the droppe ball after time t.
`v_(1) = u_(1) + "gt"`
`v_(1) = "gt"` , (downward)
For the ball thrown up, `u_(2) = 10 m//s` ,
Velocity of the ball after time t
`v_(2) = u_(2) - "gt"`
`= (40 - "gt")` , (upward)
`:.` Relative velocity of one ball w.r.t another ball
`= v_(1) - v_(2)`
`= "gt" - [-(40 - "gt")] = 40 m//s`
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