# Torque

#### serendipityfox

Homework Statement
c and d weighing 4000N and 2000N rest on a horizontal beam AB (AB is 5m length, distance to c from A is x m, distance from c to d is 1m)
if the reaction at B is twice the reaction at A, how far from A will the weight of C act.
Homework Equations
Torque = Fm
don't delete me yet, i will give an attempt in a mo'

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#### Nimarjeet Bajwa

Member warned about posting full solutions before the OP has had a chance to work through the problem.
Let x distance from A will the weight of block C act. distance between C and D is 1 m. so, distance between A and D is (x + 1)m.

according to question,
force on B = 2 × force on A
Fb = 2Fa ----(1)
but we know,from figure Fa + Fb = (4000N + 2000N)= 6000N ----(2)
now solve it Fa = 2000N and Fb = 4000N

further question said , system is rest on horizontal beam of AB . means change in moments is equal to zero.
take moments about A = 0
4000N × x + 2000N × (x + 1) - 4000 × 5 =0
6000x - 18000=0
x = 3m

#### serendipityfox

excellent explanation, i will study your method.
thanks

"Torque"

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