Angular momentum of projectile.

AI Thread Summary
The discussion focuses on calculating the angular momentum of a projectile at its highest point. The participant uses the formula for angular momentum, incorporating mass, velocity, and the angle of projection. They derive the angular momentum to be 18.75, while the expected answer is 187.5. A potential typo in the problem statement or answer sheet is suggested as the reason for the discrepancy. The calculations appear correct based on the provided values and equations.
Satvik Pandey
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Homework Statement


Find out the angular momentum of particle as it reaches the highest point about the origin in projectile?

m=1 kg angle(i)=60 degree(with horizontal) u=10 m/s g=10

Homework Equations


The Attempt at a Solution


As angular momentum=##mrvsinB ##

Here velocity at top=##ucos\theta ##

As sinB=h/r

h=rsinB

Now h=##\frac { { u }^{ 2 }{ sin }^{ 2 }\theta }{ 2g } ##

So angular momentum=##\frac { { u }^{ 2 }{ sin }^{ 2 }\theta }{ 2g } ## ##mucos\theta ##

On putting values I got
##\frac { 100{ sin }^{ 2 }(60) }{ 2\times 10 } 10cos(60)##

##5{ sin }^{ 2 }(60)10cos(60)##

##\frac { 15 }{ 4 } \times \frac { 10 }{ 2 } =18.75##
But the answer is 187.5
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Your answer looks correct. Perhaps a typo in the problem statement or answer sheet.
 
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Doc Al said:
Your answer looks correct. Perhaps a typo in the problem statement or answer sheet.
Thank you Doc Al.
 
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