Calculating Work Done by Gravity on a Ski Slope

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To calculate the work done by gravity on Bob skiing down the hill, the key is to use the vertical height of the slope rather than the hypotenuse. The work done by gravity can be calculated using the formula W = mgh, where m is Bob's mass (75 kg), g is the acceleration due to gravity (approximately 10 m/s²), and h is the vertical height (25 m). This results in a total work done of 18,750 joules. While using the incline's length and the gravitational force component is valid, the vertical height provides a simpler and direct calculation. Thus, the work done by gravity is effectively determined by the height of the hill.
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3. On a ski weekend in Colorado, Bob, whose mass is 75kg, skis down a hill that is inclined at an angle of 15º to the horizontal and has a vertical rise of 25.0m. How much work is done by gravity on Bob as he goes down the hill

for this problem i thought you had to use sohcahtoa to find out what the hypotnuse is but then i thought all you had to do is 10*the distance 25 but I am not sure which is right?
 
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rottentreats64 said:
3. On a ski weekend in Colorado, Bob, whose mass is 75kg, skis down a hill that is inclined at an angle of 15º to the horizontal and has a vertical rise of 25.0m. How much work is done by gravity on Bob as he goes down the hill

for this problem i thought you had to use sohcahtoa to find out what the hypotnuse is but then i thought all you had to do is 10*the distance 25 but I am not sure which is right?

It is enough to multiply the force of gravity, mg, with the height of the hill. You'd get the same result if you multiplied the component of the force of gravity along the incline with the length of the incline (i.e. the hypothenuse).
 
k thank you
 
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