# Work on sliding bag on aircraft

1. Nov 3, 2005

### hshphyss

Can anyone help me with this problem?

A flight attendant pulls her 70.0 N flight bag a distance of 258 m along a level airport floor at a constant speed. The force she exerts is 32.0 N at an angle of 52.0° above the horizontal. Find the work she does on the flight bag and the work done by the force of friction of the flight bag.

I was able to make a free body diagram and see that the weight of the flight bag is 70 newtons, the displacement is 258 m. But when I solved for W, which is force x displacement x cosine 52 degrees I got the wrong answer.
(70 x 258 x cos52).

2. Nov 3, 2005

### mathmike

your answer looks right to me, why do you say that it is wrong.

1345.65J

3. Nov 3, 2005

### verty

Isn't the calculation 32*cos52*258? Since the speed was constant, friction did the same amount of work.

4. Nov 4, 2005

### hshphyss

Online

Because the assignment is online, I'm able to put it in to see if I get it right or not.

5. Nov 4, 2005

### lightgrav

The 70 N weight has nothing to do withthe flight attendant's Work;
most of it is cancelled by the Surface compression Force by the Floor (F_N).
vertigo is right, there.
But Friction did a NEGATIVE amount of Work
(total external Work done on the bag = change of its KE = 0).