Answer:
3N.,
Step-by-step explanation:
Balance the moments about the pivot point, of the forces on both sides.
The moment of a force = Force × perpendicular distance from the pivot point to the line of the force.
F × 40 = 30 × 4
F = 3 N.
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2 × x = 10 × 1 + (10+20) × 3.
x = 50 meters.
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P = Pressure = Force/Area.
P = pressure at a point at a depth of h in a liquid
= ρ g h.
where ρ is the density of the liquid.
g = acceleration due to gravity.
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Hooke's law for elasticity of a spring
Force or load F = k × x.
where k = the spring constant.
x = the strain or extension of the spring after the load is attached to the spring.
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