A ball is thrown upward with a speed of 30 m/s.It will continue to rise for about
A)0.33 s.
B)1.5 s.
C)3.1 s.
D)6.1 s.

Question

Quizplus · Accepted Answer

To determine the time it takes for the ball to reach its highest point, we can use the equation:

vf = vi + at

where vf is the final velocity (at the highest point, the final velocity is 0 because the ball momentarily stops), vi is the initial velocity (which is 30 m/s upward), a is the acceleration due to gravity, which is -9.8 m/s^2 (negative because it is acting downward), and t is the time. Solving for t, we get:

t = (vf - vi) / a

At the highest point, vf = 0, so:

t = -vi / a

t = -30 m/s / -9.8 m/s^2 = 3.06 s

So the ball will continue to rise for about 3.1 seconds.

Note that choices A, B, and D are all too small or too large because they do not take into account the fact that the ball will eventually stop and begin to fall back down. Choice C is the best answer because it considers the full height of the ball's trajectory.

A Ball Is Thrown Upward with a Speed of 30