Answer
E. 14.2 seconds
Step-by-step explanation
We are going to use the Newton's law of motion.
s = ut + (1/2)gt²
Where s ⇒ height
g ⇒ acceleration due to gravity
t ⇒ time taken to reach the surface of the earth.
u ⇒ initial velocity
s = ut + (1/2)gt²
1,000 = -10t + (1/2)×-9.8×t²
10t + (1/2)×9.8×t² = -1000
4.9t² + 10t = -1000
t² + 2.0408t = 204.0816
t² + 2.0408t + 1.0204² = 204.0816 + 1.0204²
(t + 1.0204)² = 205.1228
t = +√205.1228 -1.0204 or t = -√205.1228 -1.0204
= 14.322 s = - 15.342 s
Since time can not be negative, we take the answer to be: 14.322 seconds.