Calculating Work for a Fired Projectile

Thread starter superaznnerd
Start date Jun 15, 2010
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Projectile Work

AI Thread Summary

To calculate the work done on a 4kg projectile fired at an initial velocity of 40 m/s at a 30-degree angle, the change in kinetic energy must be determined. The initial kinetic energy is zero, and the final kinetic energy is calculated using the formula KE = 0.5 * m * v^2. This results in a value of 3200 J, indicating that the work done is equal to this change in kinetic energy. The initial calculation of 5542 J was incorrect, as it did not accurately reflect the kinetic energy change. The correct work done in firing the projectile is 3200 J.

Jun 15, 2010

superaznnerd

Homework Statement

a 4kg projectile is fired on Earth with intiial velocity 40m/s at an angle of 30 degrees to the horizontal. what work was done in firing the projectile?

Homework Equations

The Attempt at a Solution

I got 5542 J. Answer is suppsoedly 3200J

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Jun 15, 2010

rock.freak667

Homework Helper

The work done is the change in kinetic energy. The mass goes from 0 to 40 m/s. So the change in kinetic energy is?

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