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Question
Explain why a cricketer moves his hands backwards while holding a catch.
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Solution
According to Newton’s second law of motion, we have the equation of motion:
F = ma = `m (trianglev)/(trianglet)` ....(i)
Where
F = Stopping force experienced by the cricketer as he catches the ball
m = Mass of the ball
Δt = Time of impact of the ball with the hand
From equation (i), it is deducible that there is an inverse proportionality between the impact force and the impact time, i.e.
`F prop 1/(trianglet)` ......(ii)
Equation (ii) demonstrates that as the time of impact increases, the force experienced by the cricketer decreases and vice versa.
During a catch, a cricketer pulls his hands backward to lengthen the time of impact (Δt). This leads to a reduction in the stopping force, which helps protect the cricketer's hands from harm.
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