Answer:

Explanation:
From the question we are told that:
Crane Length 
Crane Mass 
Arm extension at lifting end 
Arm extension at counter weight end 
Load 
Generally the equation for Torque Balance is mathematically given by



Answer:
1977.696 J
Explanation:
Given;
Weight of the box = 28.0 kg
Force applied by the boy = 230 N
angle between the horizontal and the force = 35°
Therefore,
the horizontal component of the force = 230 × cosθ
= 230 × cos 35°
= 188.405 N
Coefficient of kinetic friction, μ = 0.24
Force by friction, f = μN
here,
N = Normal force = Mass × acceleration due to gravity
or
N = 28 × 9.81 = 274.68 N
therefore,
f = 0.24 × 274.68
or
f = 65.9232 N
Now,
work done by the boy, W₁ = 188.405 N × Displacement
= 188.405 N × 30
= 5652.15 J
and,
the
work done by the friction, W₂ = - 65.9232 N × Displacement
= - 65.9232 N × 30 m
= - 1977.696 J
[ since the friction force acts opposite to the direction of motion, therefore the workdone will be negative]
Answer:
B. posititvely charged particles
Explanation:
Opposites attract to each other, and the same charge repels.
The correct answer (d.) epistemology. The major contribution of the French philosopher Rene Descartes was in the realm of epistemology. Epistemology is the theory of knowledge, including methods, validity, and its scope. It could also be concluded to separate justified fact from an opinion.
<span>The momentum of the basketball is three times that of the softball. Momentum equals mass times velocity. Therefore, if the basketball and softball are moving at the same velocity, and the basketball has three times the mass of the softball, the basketball has three times the momentum of the softball.</span>