sunsetlove 3 years ago With a force of 21 N, Lisa pulls a wagon with her little brother. The handle of the wagon makes a 15° angle with the ground. Approximately what force will move the wagon vertically upwards? Answer 28.57 N 20.28 N 5.63 N 5.44 N . 4 points Question 4 MA.912.D.9.3 A stack of K-Rails, used for highway construction, are pulled along a ramp angled 31° to the ground with a force 10,545 N as shown below. What is the horizontal force required to pull the K-Rails? Answer 5431.08 N 6336.08 N 9038.83 N

1. cse

Free body diagram incoming..

2. cse

The free body diagram for the first problem is:

3. cse

Note what you have is a force vector with magnitude 21 N at an angle of 15 degrees. And you want the vertical component of the vector e.g. the upward force

4. cse

Any vector is just the sum of its horizontal and vertical components. See:

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6. cse

So y = 21 N * sin (15) = 5.44

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*recall sin(x) = O/H

8. cse

For the second problem you do the same thing, draw a fbd, decompose the force vector

9. cwrw238

for second question horizontal force is 10545* cos 31 = 9038.83 N

10. sunsetlove

thank u guys for explaining it

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