Answer:
W = 311074.5 [J]
Explanation:
In order to solve this problem we must analyze two parts, in the first part by means of Newton's second law we can determine the acceleration of the beam, remembering that the sum of the forces is equal to the product of mass by acceleration.
∑F = m*a
F = forces acting on the beam [N]
m = mass = 425 [kg]
a = acceleration = 1.8 [m/s²]
The forces acting on the beam are the force of the crane up (positive) and the weight of the beam down (negative)
![F_{crane}-(425*9.81)= 425*1.8\\F_{crane}=4713.25 [N]](https://tex.z-dn.net/?f=F_%7Bcrane%7D-%28425%2A9.81%29%3D%20425%2A1.8%5C%5CF_%7Bcrane%7D%3D4713.25%20%5BN%5D)
Now in the second part, we use the definition of work, which is equal to the product of the force applied in the direction of displacement, that is, the product of force by distance.

where:
W = work [J]
F = force = 4713.25 [N]
d = distance = 66 [m]
![W=4713.25*66\\W=311074.5[J]](https://tex.z-dn.net/?f=W%3D4713.25%2A66%5C%5CW%3D311074.5%5BJ%5D)
Answer: The reason a light bulb glows is that electricity is forced through tungsten, which is a resistor. The energy is released as light and heat. A conductor is the opposite of a resistor. Electricity travels easily and efficiently through a conductor, with almost no other energy released as it passes.
Explanation: