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20 Physics -- Kinematics

 2. A boy stretches a stone against the rubber tape of a catapult or gulel' (a device used to detach mangoes from the tree by boys in Indian villages) through a distance of 24 cm before leaving it. The tape returns to its normal position accelerating the stone over the stretched...

 2. A boy stretches a stone against the rubber tape of a
catapult or gulel' (a device used to detach mangoes from
the tree by boys in Indian villages) through a distance
of 24 cm before leaving it. The tape returns to its normal
position accelerating the stone over the stretched length.
The stone leaves the gulel with a speed of 2.2 s. Assuming
that the acceleration is constant while the stone was being
pushed by the tape, find its magnitude. 

1 Answers

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Initial velocity(u)= 0m/s

Final velocity(v)= 2.2m/s

Displacement(d)= 24cm=0.24m

    Now,                                                                                                                                                                                                                                                                                                                                                                                            v2=u2+2as

              (2.2)2 = 02+2×a×0.24

              a = 4.84÷0.48

              a = 10.1Ansm/s2Ans



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