Final answer:
The force needed to lower a 255 kg piano from a second-story window to the ground can be determined using Newton's second law of motion. The weight of the piano is 2499 N and the tension in the tow rope is also 2499 N.
Step-by-step explanation:
The force needed to lower a 255 kg piano from a second-story window to the ground can be determined using the concept of Newton's second law of motion. The weight of the piano can be calculated using the formula weight = mass * gravity, where the mass of the piano is 255 kg and the acceleration due to gravity is approximately 9.8 m/s^2. Therefore, the weight of the piano is 255 kg * 9.8 m/s^2 = 2499 N.
The tension in the tow rope can be calculated using the force equation T = W - F, where T is the tension, W is the weight, and F is the force exerted on the piano. Since the piano is being lowered, the force exerted on it is in the opposite direction of its weight. Therefore, the tension in the tow rope is 2499 N - 0 N = 2499 N.