What Force must be exerted on the trolley for constant speed?

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To maintain constant speed on the trolley, a force of approximately 130N must be exerted. The calculations show that the parallel force is 125.3N, derived from the equation F_parallel = 900 cos(82°). The total force required is calculated using F = 125.3/cos(15°). The discussion notes that these calculations assume no friction is acting on the trolley. Overall, the calculations appear correct, but clarity on the thought process is needed.
chwala
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Homework Statement
See attached.
Relevant Equations
Mechanics
My question is on the highlighted part in red.

1717283058571.png



For the first part i have,

##F_{parallel} = 900 \cos 82^0 = 125.3N##

For the second part, i have

##F= \dfrac{125.3}{\cos 15^0} = 129.7 N ≈130N##
 
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chwala said:
For the first part i have,

##F_{parallel} = 900 \cos 82^0 = 125.3N##

For the second part, i have

##F= \dfrac{125.3}{\cos 15^0} = 129.7^0 N ≈130N##
Those answers look right to me. (I guess there is no friction). However, based on what you've written, we can't tell if you thought through it correctly.
 
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