A ball of mass 0.3 kg is released from rest at a height of 8 m. How fast is it going when it hits the ground? Acceleration due to gravity is g = 9.8 m/s2.
Group of answer choices

2.4 m/s

8.2 m/s

12.5 m/s

13.1 m/s

Respuesta :

Answer:

C. 12.5 m/s

Explanation:

h = h(0) - gt²/2

0 m = 8 m - 9.8 m/s²*t²/2

- 8 m = - 9.8 m/s²*t²/2

16 m = 9.8 m/s² * t²

t² = 16/9.8 s²

t = √(16/9.8) s

v = v(0) + gt

v = 0 +gt

v = 9.8 m/s² * √(16/9.8) s ≈ 12.5 m/s

Answer:

12.5 m/s

Explanation: