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CPHY
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My class just started the Energy unit and I would like to make sure my answers are correct to our HW questions. I am in high school Physics. Thanks.
1. Homework Statement
A student lifts their 100N book-bag 1meter in order to put it on. How much work did the student do in lifting the book-bag?
A student wears their 100N book-bag on their back and walks 20m down the hall. How much work did the student do in carrying the book-bag?
A student lowers their 100N book-bag 1m in order to take it off. How much work did the student do in lowering the book-bag?
How much work does a bodybuilder do when bench pressing 300lb 10 times?
W=f*d
1. A student lifts their 100N book-bag 1meter in order to put it on. How much work did the student do in lifting the book-bag?
W=f*d
W= (100 N)*(1 m)
W= 100 J
2. A student wears their 100N book-bag on their back and walks 20m down the hall. How much work did the student do in carrying the book-bag?
W=f*d
W=(100 N)*(20 m)
W= 2000 J
3. A student lowers their 100N book-bag 1m in order to take it off. How much work did the student do in lowering the book-bag?
W=f*d
W=(-100 N)*(1 m)
W= -100 J
4. How much work does a body builder do when bench pressing 300lb 10 times?
300 lb*10=
3000 J
1. Homework Statement
A student lifts their 100N book-bag 1meter in order to put it on. How much work did the student do in lifting the book-bag?
A student wears their 100N book-bag on their back and walks 20m down the hall. How much work did the student do in carrying the book-bag?
A student lowers their 100N book-bag 1m in order to take it off. How much work did the student do in lowering the book-bag?
How much work does a bodybuilder do when bench pressing 300lb 10 times?
Homework Equations
W=f*d
The Attempt at a Solution
1. A student lifts their 100N book-bag 1meter in order to put it on. How much work did the student do in lifting the book-bag?
W=f*d
W= (100 N)*(1 m)
W= 100 J
2. A student wears their 100N book-bag on their back and walks 20m down the hall. How much work did the student do in carrying the book-bag?
W=f*d
W=(100 N)*(20 m)
W= 2000 J
3. A student lowers their 100N book-bag 1m in order to take it off. How much work did the student do in lowering the book-bag?
W=f*d
W=(-100 N)*(1 m)
W= -100 J
4. How much work does a body builder do when bench pressing 300lb 10 times?
300 lb*10=
3000 J