Question

2 ropes are used to lower a 225 kg pieno exactly 7 m from the second story window to the ground

Answer 1

The work done by T2 is 6394 J.

The work done by a force is given by the formula:

`$$ W = F \cdot d \cdot \cos(\theta) $$`

where:

• W is the work done,
• F is the force applied (which is the tension in T2),
• d is the distance over which the force is applied (which is the height the piano is lowered),
• 
  `\(\theta\)` is the angle between the force and the direction of motion.

In this case, the angle between T2 and the direction of motion = 45 + 90 = 135 degrees.

Substituting the given values:

`$$ W = 1295 N \cdot 7 m \cdot \cos(135^o) $$`

The cosine of 135 degrees is approximately -0.7071.

So, the work done by T2 is:

`$ W = 1295 N \cdot 7 m \cdot -0.7071 = -6394 J $$`

The negative sign indicates that the work is done against the direction of motion. This means that T2 is doing negative work, or removing energy from the system, which makes sense because it's helping to lower the piano. If T2 were doing positive work, it would be adding energy to the system and lifting the piano.

The complete question: 2 ropes are used to lower a 225 kg pieno exactly 7 m from the second story window to the ground. How much work is done by T2?