Bullet passing through two holes

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AI Thread Summary
To determine the speed of a bullet passing through two rotating paper disks, the angular displacement of 24.9 degrees and the rotational speed of 819 revolutions per minute must be converted into useful units. The time taken for the bullet to travel between the two holes can be calculated using the formula that incorporates the distance and the angular speed. Once the time is established, it can be used in the equation for final position to find the bullet's speed. The key steps involve unit conversion, calculating time from angular displacement, and applying the distance to determine speed. Following these steps will yield the bullet's speed in meters per second.
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Homework Statement


so this is a classic problem...if you know what i mean.

The speed of a moving bullet can be determined by allowing the bullet to pass through two rotating paper disks mounted a distance .082m apart on the sam axle. from the angular displacement 24.9 degree of the two bullet holes in the disks and the rotational speed 819rev/min of the disks.
What is the speed of the bullet. in m/s^2


Homework Equations





The Attempt at a Solution


I try to find time from the starting point of the bullet till the second hole

time=(distance*2pi)/(full revolution of the disk*the degree)
then use that time and put it in the equation of
x final= velocity initial*time.

but didnt get it so any suggestion?
 
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First you should change the rotational speed into usefull units ie radians or degrees per second

Second, you need to use the angular displacement and the rotational speed to find the time it took for the bullet to pass from first to second piece of paper.

Third you will need to use this time and then the distance between the bits of paper to calculate the speed of the bullet. Done!
 
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