Calculating Weight and Sliding Force on a Roof | Statics Problem Solution

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The problem involves calculating the weight of a girl on a sloped roof and the force attempting to slide her off. The girl’s weight was determined to be approximately 127.39N, while the sliding force was calculated as 42.84N. The angle of the roof was found to be 19.65 degrees using trigonometric functions. It was confirmed that the weight calculation is correct, and the sliding force is accurately identified. The discussion highlights the importance of understanding the forces at play, including gravity, in determining whether the girl will slide off the roof.
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please Check my static problem

Homework Statement



a roof that has a rise of 5 meteres for every 14 meters of horizontal run. A girl stands on a scale on the roof and the scale reads 120N . what is the actual weight of the girl? what force tends to slide the girl off of the roof?

Homework Equations



tan theta=opp/adj
cos theta=adj/hyp


The Attempt at a Solution


i found the degree first, which is 19.65 degrees, I found this by using tan equation. Then I used this degree to find the weight of the grl, which is 127.39N, used cos equation. Then finally, using the degree again and tan equation, the force sliding the girl off the roof is 42.84N. I just want to know if I have the answer right? Thank you for the help!
 
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phys1618 said:

Homework Statement



a roof that has a rise of 5 meteres for every 14 meters of horizontal run. A girl stands on a scale on the roof and the scale reads 120N . what is the actual weight of the girl? what force tends to slide the girl off of the roof?

Homework Equations



tan theta=opp/adj
cos theta=adj/hyp


The Attempt at a Solution


i found the degree first, which is 19.65 degrees, I found this by using tan equation. Then I used this degree to find the weight of the grl, which is 127.39N, used cos equation. Then finally, using the degree again and tan equation, the force sliding the girl off the roof is 42.84N. I just want to know if I have the answer right? Thank you for the help!
Pretty close. The girl's weight is correct. Also, there is a 42.8N force trying to slide her down the roof. What is the nature of that force? It may not be successful in making her slide if there is enough ________ available to offset this force.
 


are you talking about gravity??
 
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