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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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प्रश्न

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

योग
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उत्तर

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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अध्याय 3: Laws of Motion - Exercise 3 (E) [पृष्ठ ८१]

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सेलिना Concise Physics [English] Class 9 ICSE
अध्याय 3 Laws of Motion
Exercise 3 (E) | Q 15.1 | पृष्ठ ८१

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