Question

For a body thrown vertically upwards from the ground, if the time interval between the two instants when the body is at a height of \(60\,\text{m}\) is \(4\,\text{s}\), then the maximum height reached by the body is \[ (\text{Acceleration due to gravity}=10\,\text{m s}^{-2}) \]

• A. \(150\,\text{m}\)
• B. \(90\,\text{m}\)
• C. \(120\,\text{m}\)
• D. \(80\,\text{m}\)

Hint:

For vertical projection, \[ \boxed{H=\frac{u^2}{2g}.} \] If a body reaches the same height twice, the difference between the two times can be obtained from the roots of the corresponding quadratic equation.

Answer 1

The Correct Option is D