A ball is thrown vertically upwards with a velocity of 25 text ms-1 from the top of a tower of height 30 m . How long will it travel before it hits ground?

Question

A ball is thrown vertically upwards with a velocity of 25 text ms-1 from the top of a tower of height 30 m . How long will it travel before it hits ground? (A) 6 s (B) 5 s (C) 4 s (D) 12 s

Tardigrade Admin · Accepted Answer

s=ut+(1/2)gt2 ∴ 30=-25t+(10/2)t2 or t2-5t-6=0 or (t-6)(t+1)=0 ∴ t=6 s

Q. A ball is thrown vertically upwards with a velocity of $25 m s^{- 1}$ from the top of a tower of height $30 m$ . How long will it travel before it hits ground?

6 s

5 s

4 s

12 s

10 s

$s = u t + \frac{1}{2} g t^{2}$
$∴$ $30 = - 25 t + \frac{10}{2} t^{2}$
or $t^{2} - 5 t - 6 = 0$
or $(t - 6) (t + 1) = 0$
$∴$ $t = 6 s$

Q. A ball is thrown vertically upwards with a velocity of 25ms−1 from the top of a tower of height 30m . How long will it travel before it hits ground?

6 s

5 s

4 s

12 s

10 s

s=ut+21​gt2 ∴ 30=−25t+210​t2 or t2−5t−6=0 or (t−6)(t+1)=0 ∴ t=6s

Q. A ball is thrown vertically upwards with a velocity of $25 m s^{- 1}$ from the top of a tower of height $30 m$ . How long will it travel before it hits ground?

$s = u t + \frac{1}{2} g t^{2}$
$∴$ $30 = - 25 t + \frac{10}{2} t^{2}$
or $t^{2} - 5 t - 6 = 0$
or $(t - 6) (t + 1) = 0$
$∴$ $t = 6 s$