Question

a building has 10 floors with a floor height of 3 meters each. a ball is dropped from the top of the building. find the time taken by the ball to reach each floor. (use the formula s = ut+(1/2)at^2 where u and a are the initial velocity in m/sec (= 0) and acceleration in m/sec^2 (= 9.8 m/s^2)).

Answer 1

This is a question on kinematics.

Since the ball is dropped from the top, the initial velocity is 0.

Given that we have 10 floors each of 3m,the height travelled by the ball is :

3 × 10 = 30 m

From the equation above :

S = ut + 1/2gt²

u = the initial velocity = 0

S = height covered = 30m

g = 9.8

Doing the substitution :

30 = 0 × t + 0.5 × 9.8 × t²

30 = 4.9t²

t² = 30/4.9 = 6.1224

t = √6.1224

t = 2.47 seconds

Answer 2

Answer:

#include <stdio.h>

#include<math.h>

int time(float t);

int s=3;

float a=9.8;

int main()

{

float t;

t=sqrt((2*s)/a);

printf("The time taken to reach floor is %f\n",t);

time(t);

}

int time(float t)

{

   float t1;

   s=s+3;

   if(s<=30)

   {

       t1 = sqrt((2*s)/a);

       printf("The time taken to reach floor is %f\n",t1-t);

       time(t1);

   }

}

Explanation: