Calculating Work Done by a Force on a Block

AI Thread Summary
To calculate the rate at which the force does work on the block, the correct approach involves using the formula for power, which is the product of the force component in the direction of motion and the velocity. The force should be multiplied by the cosine of the angle to find the effective force acting along the horizontal direction. If the force were applied parallel to the surface, the angle would be zero, and the cosine would equal one, simplifying the calculation. It's essential to understand the definition of work and identify the relevant quantities to determine the work done per second accurately. The discussion emphasizes the importance of considering the angle of the applied force in relation to the direction of motion.
faet
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Okay, the question is:

A 190kg block is pulled at the constant speed of 4.8m/s across a horizontal floor by an applied force of 130N directed 37deg above the horizontal. What is the rate at which the force does work on the block? (in W)

to find this, would i multiply 130by cos(37), then by 4.8 to get work/sec?
 
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A couple of points;

- Consider what would happen if the force was applied parallel to the surface (so the angle is zero). Do you still think you should take the cosine?
- Review the definition of work. What quantities do you then need to calculate to find the amount of work done per second?

Also, this thread should be moved to the Homework Help section.

Claude.
 
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