A bullet shot straight up returns to its starting point in 10 s.What is the initial speed of the bullet,assuming negligible air resistance?
A)9.8 m/s
B)25 m/s
C)49 m/s
D)98 m/s

Question

Quizplus · Accepted Answer

When a bullet is shot straight up, its initial velocity is equal to the final velocity (zero) at its highest point of motion. Therefore, we can use the equation:

v = u + at

where v = 0 (final velocity), u is the initial velocity, a is the acceleration due to gravity (9.8 m/s^2), and t is the time taken to reach the highest point (which is equal to the time taken to return to the starting point).

Thus, we have:

0 = u - 9.8(10)

After solving for u, we get:

u = 49 m/s

Therefore, the initial speed of the bullet is 49 m/s. Hence, the correct answer is (C).

A Bullet Shot Straight Up Returns to Its Starting Point