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[Eng] Physics Question (Mechanics) HELP!!!

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Physics Question (Mechanics) HELP!!!

does anyone know how to do question 1c?

Apiece of concrete falls from a height 40 m above the ground. Neglect airresistance and take g to be 9.81 m s–2.
(a)
How long does it take for the concrete toreach the ground?
(2marks)

(b)
What is the speed of the concrete when itreaches the ground?
(2marks)

(c)
Now, the concrete is thrown horizontally with 15 m s-1 by a boy asshown in figure 1.2. The concrete will finally drop to the ground. Let x m be the shortest distance between theconcrete and the building. If a car is moving with a constant speed of y m s-1 and it is hit by theconcrete finally. Find the value of y.
(4 marks)

Figure 1.1 and 1.2 are as shown in the documents.

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Help!!!

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PUSH

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我唔知架車係米舊石屎下面
水平拋體 既話 就用a部個 跌落地時間 2.86s
x= 2.86 x 15 = 42.84m

y= 42.84/2.86 = 14.98ms^-1

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oh  thx

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