A ball is thrown downward with an initial velocity of 12.1 m/s. How long will it take to reach a velocity of -24.5 m/s? (Negative indicates the downward direction) A) 1.27 s
B) 3.73 s
C) there is not enough i for to solve the problem
D) 14.6 s

Explanation:

The sig figs are off in the answer (unless you use -9.81 for the acceleration due to gravity. My classes always use -9.8, which is 2 sig figs. But nevertheless, we can solve it!) Use the velocity formula:

where vf is the final velocity, v0 is the initial velocity, a is the acceleration due to gravity, and t is the time in seconds. Filling in, using the fact that both the velocities are negative since the ball is going down:

-24.5 = -12.1 +(-9.8)t or

-24.5 = -12.1 - 9.8t and

-12.4 = -9.8t and divide to get that

t = 1.27 sec

hi there!

your question asks at which segment does freezing occur.

since we're talking about water, the freezing point of water will be 32 degrees fahrenheit or below.

hope this ! ~

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