A body is thrown vertically up with an initial velocity of 60 m/s. If acceleration due to gravity g = $10 m / s^{2}$ , what is the time taken to reach a height of 100 m. [3 MARKS]

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Solution

Equations: 1 Mark
Finding both answers: 2 Marks

Here,
$u = 60 m / s, S = 100 m, a = - 10 m / s^{2}$
$S = u t + \frac{{a t}^{2}}{2}$
$100 = 60 t - \frac{10 \times t^{2}}{2}$
$t^{2} - 12 t + 20 = 0$
$t = 2 s a n d 10 s$

During the whole journey the body will be at a height of 100m at two different times. At t =2 s and t = 10 s.

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A body is thrown vertically up with an initial velocity of 60 m/s. If acceleration due to gravity g = 10 m/s2, what is the time taken to reach a height of 100 m. [3 MARKS]

Equations: 1 Mark Finding both answers: 2 Marks Here, u=60 m/s,S=100 m,a=−10 m/s2 S=ut+at22 100=60t−10 × t22 t2−12t+20=0 t=2 s and 10 s During the whole journey the body will be at a height of 100m at two different times. At t =2 s and t = 10 s.

A body is thrown vertically up with an initial velocity of 60 m/s. If acceleration due to gravity g = $10 m / s^{2}$ , what is the time taken to reach a height of 100 m. [3 MARKS]