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How Long Will a Stone Take to Fall to the Ground from the Top of a Building 80 M High

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Question

How long will a stone take to fall to the ground from the top of a building 80 m high 

Sum
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Solution

Height, s = 80m

g = 10 m/s2

Using the second equation of motion,

S = ut + (1/2) gt2

Or, 80 = 0+ (1/2) (10) (t) 2

Or, (t) 2 = 16

Or, t = 4s

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Chapter 3: Laws of Motion - Exercise 3 (E) [Page 81]

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Selina Concise Physics [English] Class 9 ICSE
Chapter 3 Laws of Motion
Exercise 3 (E) | Q 15.1 | Page 81

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