Question

An astronaut on a foreign planet uses a cannon to launch a ball straight up at the top of a 56-meter-high cliff with a speed of 4.9 m/s. As the ball hits the ground at the base of the cliff, the astronaut measures the speed to be 19.3 m/s. What is the acceleration of gravity on this planet?

A. 9.8 m/s²
B. 10.2 m/s²
C. 11.6 m/s²
D. 12.9 m/s²

Answer 1

The acceleration of gravity on the foreign planet is 12.9 m/s².

Step-by-step explanation:

To determine the acceleration due to gravity on the foreign planet, we can use the equation:

v^2 = u^2 + 2as

Where:

v = final velocity = 19.3 m/s

u = initial velocity = 4.9 m/s

s = displacement = 56 m

Substituting these values into the equation, we get:

(19.3)^2 = (4.9)^2 + 2(a)(56)

Simplifying the equation, we find:

a = 12.9 m/s^2

Therefore, the acceleration of gravity on this planet is 12.9 m/s^2. Therefore, the correct answer is D. 12.9 m/s².