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When a 20 kg explosive detonates and sends a 5 kilogram piece traveling to the right at 105 m/s

what is the speed and direction of the other 15 kilogram piece of the explosive!

User Carlos Nunes
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1 Answer

9 votes
9 votes

Answer:

speed: 35m/s

direction: left

Step-by-step explanation:

Assuming the right side is the positive direction:

before explosion:

P = mv = 0

after explosion:

P' = 15P + 5P

(Set the velocity of the 15kg piece after explosion as v1' and the velocity of the 5kg piece after explosion as v2')

P' = 0.75mv1' + 0.25mv2'

P' = (15kg)v' + (5kg)(105m/s)

P' = 525kg/m/s + (15kg)v1'

P = P'

525kg/m/s + (15kg)v1' = 0

(15kg)v1' = -525kg/m/s

v1' = -35m/s

speed = |-35| = 35m/s

direction is to the left since the right side is the positive direction.

User Raouf
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