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Question
A force of 600 dynes acts on a glass ball of mass 200 g for 12 s. If initially, the ball is at rest, find
- Final velocity
- Distance covered.
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Solution
F = 600 dyne = 600 g cms−2
m = 200 g
Acceleration = a =`"F"/"m"=(600"gcms"^-2)/(200"g")`
a = 3 cms−2
Also time = t = 12 s
Initial velocity = u = 0
1. Final velocity = v = ?
v = u + at
v = 0 + 3 (12)
v = 36 cms−1
2. Distance covered = S = ?
v2 – w2 = 2a s
(36)2 − (0)2 = 2(3)s
S = `(36xx36)/6` = 36 × 6 = 216 cm
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