Calculating Work and Speed on a Frictionless Incline

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The discussion focuses on calculating the work done by various forces on an 18 kg block moving up a 32° frictionless incline. The horizontal force of 150 N does positive work as it moves the block 2.1 m, while the gravitational force does negative work, calculated using the component of gravity along the incline. The normal force does no work since it acts perpendicular to the direction of displacement. The participant confirms that the work done by the normal force is zero. The final speed of the block can be determined using the work-energy principle, considering the net work done on the block.
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Homework Statement


How much work is done by the horizontal force Fp = 150 N on the 18 kg block of the figure when the force pushes the block 2.1 m up along the 32° frictionless incline? (b) How much work is done by the gravitational force on the block during this displacement? (c) How much work is done by the normal force? (d) What is the speed of the block (assume that it is zero initially) after this displacement? m/s

Homework Equations


[Hint: Work-energy involves net work done.]http://www.webassign.net/gianpse4/7-29.gif

The Attempt at a Solution


I know the answer to (c) is zero and I know how to do the problem when the force is parallel to the incline, but I am not sure how the values change with the force being at an angle.
 
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For a its just Force x distance

For b you have to calculate the force of gravity which is mgsin\theta then you multiply by the distance

And C its zero
 
Thanks, I figured it out ;)
 

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