A body dropped from a tall building covers,two floors in the first second.If all the floors are of equal height,the number of floors it covers in the next one second is

Dear Chakrala,

Let height of 1 floor is h,

u = 0 , so,  v  = u + at     (a = g =10 m/s2 )

                 v = 10 * 1 = 10 m/s

  Now,    v² - u² = 2as

 so,     100  = 2 * 10 * s

    or,   s = 5 m

which implies height of each floor is  = 5 / 2 =  2.5 m

For 2 sec. , distance covered is  s= ut + 1/2 at² = 0 + 10 * 4/2 = 20m

So, we have Distance covered in 2nd second = 20 - 5 = 15 m

Henc e, No. of floor = 15/2.5 = 6

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