What is the force on the exerted edge of the cap

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A student exerts a force of 40 N on a bottle opener to remove a cap and is trying to determine the force exerted on the cap's edge. The torque calculations involve using the formula t = r * d, where the distance from the pivot point is crucial. The student initially miscalculated by considering the wrong pivot point, leading to confusion about the resulting force. After correcting the approach, it was established that the force on the cap edge is 240 N, calculated using the relationship between torque and distance. The discussion highlights the importance of accurately identifying pivot points in torque problems.
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Homework Statement


To remove a bottle cap, a student exerts a force of 40 N on the opener. What is the force on the exerted edge of the cap by the opener?

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Homework Equations



sigma(Tccw) = sigma(Tcw)
t=r*d

The Attempt at a Solution



t= 40*.35
t= 40*.30
+
= 26 n*m

i know its supposed to be in Newtons but I am not sure how to calculate force when torque is involved
 
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Since the torque is the same, force*dist is the same in both cases.
 
im still confused
i got torque for the whole bottle opener (t=40*.3) and i got torque for the opener coming in contact with the edge of the lid (t=40*.25)
the answer is 240 N but i come no where close to it :cry:
 
Torque of 40 N is acting at a dist of 30 cm from the point = torque of F acting at a dist of 5 cm from the pint =>
F*0.05 = 40*0.30 =>
F = 240. (in N)
 
argh i got it, I was thinking the start of the handle was a pivot so i was backwards in thinking for terms of distance
thanks for clearing it up :)
 
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