Question

A plank is balanced on a pivot, where it is placed 140 m from left edge of the plank. There are masses of 12 kg and 28 kg on each side of the plank. Find the distance from the pivot to right edge of the plank

Answer 1

Explanation:

ANSWER

Now from the laws of equilibrium

ΣF = 0

R

1

−40g−45g+R

2

=0

R

1

+R

2

=85g

850N

and

Στ=0

R

1

×0.5−40g ×2.5−45g ×3.5+R

2

×4.5 = 0

R

1

+9R

2

=5150

solving for R

1

and R

2

R

1

= 312.5 N

R

2

= 537.5 N