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A body starts slipping down on an incline plane and moves half meter in half second .How long will it take to next half metre?

pallavi pradeep bhardwaj , 14 Years ago

Grade 12

2 Answers

Badiuddin askIITians.ismu Expert

Last Activity: 14 Years ago

Dear pallavi

motion for 1/2 meter

so s= ut +1/2 a t²

1/2 =0+1/2 * a *(1/2)²

a=4 m/sec2

now motion for 1 meter

s= ut +1/2 a t²

1=0+ 1/2 * 4 *t²

t=1/ √2

so time taken for next 1/2 meter is t'=1/ √2 -1/2 sec

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Vineeth Chennabhoina

Last Activity: 7 Years ago

First we find the acceleration of the body. For the first half second, the distance covered is half a meter. As we solve s= ut + 1/2at², we get a=4m/s². Intially the body didn’t have any velocity, but as we go through the first half second, the body gains a velocity v= u +at , as this is the velocity the body gains at the end of first half second and it has no initial velocity, substituting a=4 and t=0.5, we get v=2 m/s.

Finally, the time taken for the second half second will be

s = ut + ½at^2. Here s is 0.5, u=2m/s, a=4m/s. We get a quadratic in t. Which would be

4t² + 4t – 1 = 0 Solving by the finding roots of x, we get 1.656/8, which is 0.207 seconds, rounding it off to 0.21 seconds.