Problem-Solving: Calculating Forces on Moving Objects [4 Examples]

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The discussion centers on solving four physics problems related to calculating forces on moving objects. Participants are asked to determine the resistive force on a supertanker, the lift force and air resistance on a helicopter, the minimum pulling force needed by a clown to pull his feet out from under himself, and the tension in two wires supporting a sign. The thread emphasizes the need for participants to show their work for feedback rather than simply providing answers. Overall, the focus is on collaborative problem-solving in physics.
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Can anyone tell me the answers to these problems because I cannot check them b/c they are not in the back of the book. I attempted them but i feel like they are wrong.

1. a supertanker (mass= 1.70 x 10^8 kg) is moving with a constant velocity. Its engine generates a forward thrust of 7.40 x 10^5 N. Determine (a) the magnitude of the resistive force exerted on the tanker by the water and (b) the magnitude of the upward buoyant force exerted on the tanker by the water.

2. A helicopter is moving horizontally to the right at a constant velocity. The weight of the helicopter is W = 53,800 N. The lift force generated by the rotating blade makes an angle of 21 degrees with respect to the vertical. (a) what is the magnitude of the lift force? (b) determine the magnitude of the air resistance that opposes the motion.

3. A circus clown weights 890 N. The coefficient of static friction between the clown's feet and the ground is .53. He pulls vertically downward on a rope that passes around three pulleys and is tied around his feet. What is the minimum pulling force that the clown must exert to yank his feet out from under himself?

4. A 43.8 kg sign is suspended by two wires. Wire one makes a 43 degree angle with respect to the ceiling and wire 2 makes a 55 degree angle with the ceiling. Find the tension in wire 1 and wire 2.
 
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