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3 years ago

10

As you are cycling to the Q center one spring day, you pass the construction site at Gant and stop to watch a few minutes. A cra

ne holds bricks on a pallet to an upper floor of the building. Suddenly, a brick falls off the rising pallet. You clock the time it takes to hit the ground at 2.5 s. From how high did the brick fall?

1 answer:

Rama09 [41]3 years ago

7 0

Answer:

30.63 m

Explanation:

Using y = ut + 1/2gt² where u = initial speed of block = 0 m/s, g = acceleration due to gravity = 9.8 m/s² and t = time of fall = 2.5 s and y = height of fall.

So, substituting the values of the variables into the equation, we have

y = ut + 1/2gt²

y = 0 m/s × 2.5 s + 1/2 × 9.8 m/s² × (2.5 s)²

y = 0 m + 4.9 m/s² × 6.25 s²

y = 0 m + 30.625 m

y = 30.625 m

y ≅ 30.63 m

So, the brick fell 30.63 m

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