How Do You Calculate Power and Work in Physics Problems?

  • Thread starter ACLerok
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In summary, one problem involves finding the power produced by taking the time derivative of an equation. The other problem involves finding the work done on a baseball by a person, where the terms of force, velocity, and angle are all functions of time. The total work can be found by using the kinetic energy of the ball. However, this may require knowledge of calculus which may not be required for the course.
  • #1
ACLerok
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The answer to the first part of one of the problems is:
W=F*v*t*cos(theta)
The second asks me to take the time derivative of this equation in order to find the power produced. How do I do this??

Also, say a baseball leaves a pitcher's hand at a speed of v and the mass of the baseball is M_baseball. You can ignore air resistance. What is the work done on the ball by the guy??
 
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  • #2
Which terms are functions of time?
 
  • #3
f, v, and theta should all be functions of time (usually t). Simply take the derivative with respect to t.

For the second part of the problem, you can use the fact that the total work is equal to the kinetic energy of the ball.
 
  • #4
sorry, I've never taken calculus.. i don't undersatnd what youa re saying/
 
  • #5
Your original statement of the problem was "The second asks me to take the time derivative of this equation in order to find the power produced."

If you have never taken calculus then you cannot do this problem and probably should not be taking this course.
 
  • #6
can u please just tell me the answer?? my prof. says calculus is not required for my physics course. its just that we haven't covered this material yet and I'm moving ahead..

anyone?
 
Last edited:

1. What is the formula for calculating work?

The formula for calculating work is W = F * v * t * cos(theta), where W is the work (measured in joules or newton-meters), F is the force applied (measured in newtons), v is the velocity (measured in meters per second), t is the time (measured in seconds), and theta is the angle between the force and the displacement.

2. How does the force affect the work calculation?

The force has a direct impact on the work calculation. The greater the force applied, the more work will be done. This is because work is defined as the product of force and displacement.

3. What does the velocity represent in the work formula?

The velocity, represented by the letter v, is the speed at which an object is moving. It is measured in meters per second and is a crucial component in calculating work as it affects the amount of force required to move an object and the distance it travels.

4. How does the angle theta affect the work calculation?

The angle theta, represented by the Greek letter, affects the work calculation as it represents the angle between the applied force and the displacement of the object. If the force is applied at an angle, only the component of the force that is in the direction of the displacement will contribute to the work done.

5. What are the units of measurement for work?

The units of measurement for work are joules (J) or newton-meters (N*m). These units are derived from the components of the work formula, with force measured in newtons (N), velocity in meters per second (m/s), and time in seconds (s).

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