The Speed of a Falling Ball

A student drops a ball from a window 3.5 m above the sidewalk. How fast is it moving when it hits the sidewalk?

Final answer:

When the ball is dropped from a window 3.5 meters above the ground, it accelerates due to gravity. Thus, the ball hits the sidewalk at a velocity of 8.2 m/s.

Explanation:

When a student drops a ball from a window 3.5 m above the sidewalk, the ball free falls and accelerates downwards due to gravity. The acceleration due to gravity is constant, at 9.8 m/s². To find out the velocity of the ball when it hits the sidewalk, we can employ the following key physics equation: v = √(u^2 + 2gd) Here, v represents the final velocity of the ball (velocity when it hits the sidewalk), u is the initial velocity (0 m/s; the ball was dropped, not thrown), g is the acceleration due to gravity (9.8 m/s²), and d is the distance the ball travels (3.5 m). v = √(0^2 + 2*9.8*3.5) v = √(6.8) v = 8.2 m/s Thus, the correct answer is 8.2 m/s, which is the final velocity of the ball when it reaches the sidewalk.

a. What is the distance the ball travels before hitting the sidewalk? b. What is the acceleration of the ball as it falls? a. The distance the ball travels before hitting the sidewalk is 3.5 meters. b. The acceleration of the ball as it falls is 9.8 m/s² due to gravity.
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