Question

A projectile is thrown horizontally from a 490m high cliff with a velocity of 100 ms'. The time taken by projectile to reach the ground is
A. 2.5
B. 5.0
C. 7.5 s
D. 105​

Answer 1

Answer:

10s

Explanation:

• S=vt+1/2ₓat²
• 490=(0ₓt)+1/2ₓ9.8ₓt²
• 490ₓ2/9.8=t²
• t=$\sqrt{100}$
• t=10s Answer.

Answer 2

Answer:

The time taken by projectile to reach the ground is 10 sec

Explanation:

To find:

Time taken by projectile.

Given:

The height of the cliff when a projectile is thrown horizontally is 490m

The velocity of the projectile is 100ms'

The time taken by projectile to reach the ground is

$s = ut + \frac{1}{2} a {t}^{2}$

$s = 490 \\ u = 0 \\ a = 9.8$

$490 = 0 \times t + \frac{1}{2} \times 9.8 \times {t}^{2} \\ \frac{490 \times 2}{9.8} = {t}^{2} \\ \frac{980}{9.8} = {t}^{2} \\ {t}^{2} = 100 \\ t = \sqrt{100} \\ t = 10sec$

The time taken by projectile to reach the ground is 10 sec

The project code is #SPJ2