SOLUTION: When a bullet is fired from a loosely held rifle,the ratio of the mass of the bullet to that of the rifle equals the negative of the reciprocal of the ratio of the velocity of the

Algebra ->  Proportions -> SOLUTION: When a bullet is fired from a loosely held rifle,the ratio of the mass of the bullet to that of the rifle equals the negative of the reciprocal of the ratio of the velocity of the       Log On


   

Question 1197642: When a bullet is fired from a loosely held rifle,the ratio of the mass of the bullet to that of the rifle equals the negative of the reciprocal of the ratio of the velocity of the bullet to that of the rifle.If a 3.0kg rifle fires a 5.0g bullet and the velocity of the bullet is 300m/s,what is the recoil velocity of the rifle?
Thank you for answer.
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
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When a bullet is fired from a loosely held rifle,
the ratio of the mass of the bullet to that of the rifle equals
the negative of the reciprocal of the ratio of the velocity of the bullet to that of the rifle.
If a 3.0kg rifle fires a 5.0g bullet and the velocity of the bullet is 300m/s,
what is the recoil velocity of the rifle?
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Write the proportion as you read the problem

    m%5Bb%5D%2Fm%5Br%5D = -v%5Br%5D%2Fv%5Bb%5D,

where "m" means the mass, v means velocity, index "b" means bullet, index"r" means riffle.


In the proportion, substitute the given values

    5%2F3000 = v%5Br%5D%2F%28%28-300%29%29


and find the unknown 

   v%5Br%5D = %285%2A%28-300%29%29%2F3000 = - 0.5 m/s.    ANSWER


The sign " - " (minus) means that velocity of the riffle is directed opposite to that of the bullet.

Solved.