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A fuse (a special cord, burning with a l...

A fuse (a special cord, burning with a low rate) is used to iginite a bomb. The flame propagates with constant velocity v=0.8 cm/sec. what is the length of the fuse so that the man could run off to a safe distance s=120m, while the flame will not reach the bomb ? the velocity of person `v_(1)=4 m//sec`

A

32 cm

B

8 cm

C

12 cm

D

24 cm

Text Solution

Verified by Experts

The correct Answer is:
B
`t=120/4 = 30 sec`.
`l=vt=0.8xx30 =24 cm`
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