Work on an incline with friction.

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SUMMARY

Daphne pushes a 22.0 kg crate up a 30.0-degree incline in two scenarios: first, on a frictionless surface, and second, with a coefficient of kinetic friction of 0.200. In the first scenario, she does 1,080 J of work, calculated using the formula W = Fd cos(theta). In the second scenario, the work done is 1,451.4 J, factoring in the force of kinetic friction which opposes the motion. The normal force is determined to be 215.6 N, which is essential for calculating the frictional force.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with the concepts of work and energy
  • Knowledge of friction and normal force calculations
  • Proficiency in trigonometry, specifically cosine functions
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  • Study the calculation of work done against friction in inclined planes
  • Learn about the dynamics of motion on inclined surfaces with friction
  • Explore the relationship between normal force and frictional force
  • Investigate the effects of different coefficients of friction on work calculations
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d.tran103
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Okay, I am stuck on this problem that comes in two parts. Please help! Thanks!

Homework Statement



Part 1) Daphne pushes a 22.0 kg crate up a frictionless 30.0 degree incline a distance along the incline of 10.0 m at constant velocity. How much work did Daphne do?

Part 2) Daphne now pushes a 22.0 kg crate up the 30.0 degree incline with a coefficient of kinetic friction of 0.200. As before, she pushes the crate a distance up the incline of 10.0 m at constant velocity. How much work did Daphne do?

Homework Equations


W=Fdcos(theta)

The Attempt at a Solution


Part 1) I'm 100% confident in the answer I got for part 1, w=(9.8 m/ss)(22 kg)(10.0 m)(cos60), w=1.08E3 J.
Part 2) This is where I'm stuck. How does friction apply to this? It changes the force but it isn't working for me. I know the answer is 1451.4J but can't figure out how to get it. Thanks!
 
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Force of kinetic friction of the moving body = coefficient of kinetic friction * normal force from the surface on the body.
Direction of the force of friction is against the direction of movement.
 
So is 431.2 N my diagonal component and 215.6 my vertical component, making 215.6 the normal force? Thanks!
 

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