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BARSIC [14]
4 years ago
15

77. There is a 250-m-high cliff at Half Dome in Yosemite National Park in California. Suppose a boulder breaks loose from the to

p of this cliff. (a) How fast will it be going when it strikes the ground? (b) Assuming a reaction time of 0.300 s, how long a time will a tourist at the bottom have to get out of the way after hearing the sound of the rock breaking loose (neglecting the height of the tourist, which would become negligible anyway if hit)? The speed of sound is 335.0 m/s on this day.
Physics
1 answer:
lisabon 2012 [21]4 years ago
8 0

Answer:70 m/s or 6.84 s

Explanation:

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