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resolving forces (1 Viewer)
- Thread starter fgzz
- Start date
liamkk112
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- Mar 26, 2022
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- 2023
resolve forces really means take the sum of forces (which is equal to ma by newton's 2nd law)
now by drawing a diagram, you can see that:
- there is a force R in the j direction
- there is a force -mgsin(theta) in the i direction
- there is a force -mgcos(theta) in the j direction
so summing the forces you get F = -mgsin(theta)i + (R-mgcos(theta))j
but, the object is not accelerating in the j direction since it is sliding down the slope in the i direction. so the forces balance in the j direction, which gives that
R-mgcos(theta) = 0, and so F = -mgsin(theta)i
now by drawing a diagram, you can see that:
- there is a force R in the j direction
- there is a force -mgsin(theta) in the i direction
- there is a force -mgcos(theta) in the j direction
so summing the forces you get F = -mgsin(theta)i + (R-mgcos(theta))j
but, the object is not accelerating in the j direction since it is sliding down the slope in the i direction. so the forces balance in the j direction, which gives that
R-mgcos(theta) = 0, and so F = -mgsin(theta)i