What is the work dont by force?

👨🏻‍🏫 學術台物理學

[匿名]

2008-04-05 10:22 pm

A constant force of 25 N is applied as shown to a block which undergoes a displacement
of 7.5 m to the right along a frictionless surface while the force acts. What is the work
done by the force?

A) zero joules B) +94 J C) -94 J D) +160 J E) -160 J

The answer is E. How would I get this answer?

ahh im so lost!

更新1:

im sorry there is an inclined plane of 30 degrees.

回答 (5)

[匿名]

2008-04-05 10:32 pm

✔ 最佳答案

work = force * distance
work = 25N * 7.5m
work = 187.5 newton's per meter
newton per meter = joule
work = 187.5 joules

if it has to be e, then there must be either a typo or something missing in the question. is this block moving on an inclined plane or already possessing of some sort of momentum?

👍 0 👎 8

[匿名]

2014-09-28 3:42 pm

Work = F*s*cos

25*7.5*cos150 = -162 N-m

cos(150) because the force is directed on the other side

👍 2 👎 1

[匿名]

2008-04-08 8:47 pm

i like youporn

👍 2 👎 2

[匿名]

2008-04-05 10:30 pm

The expression for work is just force * displacement. W=Fx. The force has to be in the direction of the displacement. It probably depends on what the diagram shows, but find out what amount of the force is in the direction of the displacement, and then multltiply.

👍 0 👎 3

billrussell42

2008-04-05 10:31 pm

the answer is 187.5
25N x 7.5 m = 187.5 N-m

Unless the force is being applied at an angle to the motion, which we can't see.

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