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sunsetlove
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
Free body diagram incoming..
The free body diagram for the first problem is:
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
Any vector is just the sum of its horizontal and vertical components. See:
So y = 21 N * sin (15) = 5.44
For the second problem you do the same thing, draw a fbd, decompose the force vector
for second question horizontal force is 10545* cos 31 = 9038.83 N
thank u guys for explaining it