A weight of 1200 N rests on a lever at a point 0.50 m from a support. On the same side of the support, at a distance of 3.0 m from it, an upward force with magnitude F is applied. Neglect the weight of the board itself. If the system is in equilibrium, what is F?
2006-10-29 13:08:09 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
equilibrium means the clockwise and counterclockwise moments are teh same.
1200x0.5 = F x 3
F=200N
2006-10-29 13:10:35 · answer #1 · answered by Anonymous · 0⤊ 0⤋
You have two Forces which must meet equilibrium,
so F1 = -F2. Force = md, where m=mass and d=distance,
so m1d1 = -m2d2.
Here, F1 = 1200x0.5 =600 units, you need m2d2 to also equal 600 units.
F2 = m2x3.0 = 600, so m2=200 N. If your instructor is a stickler for directionality, you need to apply the force in an opposite direction, so apply -200 N of F.
You notice this is a lower absolute number, meaning the lower force needed due to the increased difference is an application of "leverage". That's why a longer screw driver, for example, can pry open a paint can easier than a shorter screw driver.
2006-10-29 21:17:44 · answer #2 · answered by Action 4 · 0⤊ 0⤋
Action has the variable names all messed up but did give the right answer. Said "You have two Forces which must meet equilibrium" should have said 2 torques.
Should have said T1 = -T2, and f1d1 = - f2d2.
2006-10-29 22:22:13 · answer #3 · answered by sojsail 7 · 0⤊ 0⤋
do your OWN homework
2006-10-29 21:09:33 · answer #4 · answered by Kami 2 · 0⤊ 2⤋