1. Tardigrade
  2. Question
  3. Physics
  4. A stone is dropped from a certain height which can reach the ground in 8 sec . It is stopped after three seconds of its fall and then is again released. The total time taken by the stone to reach the ground will be ( g=10 m / s 2 )

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A stone is dropped from a certain height which can reach the ground in 8 sec . It is stopped after three seconds of its fall and then is again released. The total time taken by the stone to reach the ground will be ( $g=10 m / s ^2$ )

Motion in a Straight Line

Solution:

Height from which the stone is dropped
$h=\frac{1}{2} g t^2=\frac{1}{2} \times 10 \times 8^2=320 m$
The distance of fall of stone for 3 seconds
$h_1=\frac{1}{2} \times 10 \times 3^2=45 m$
The remaining distance for the falling stone
$=320-45=275 m$
If $t^{\prime}$ is the time taken to fall the distance 275 m , then
$t^{\prime}=\sqrt{\frac{2 \times 275}{10}}=\sqrt{55}=7.416 s=7.4 s$
Total time $=3+7.4=10.4 s$