A spring popper toy with a mass of 25 g is compressed by 35 mm. The...

 

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A spring popper toy with a mass of 25 g is compressed by 35 mm. The spring constant is 100 N/m a) If no energy is lost, how fast will it be going when the spring is relaxed? (2 points) b) How high would it go if there were no air resistance? (2 points) c) In reality, air resistance exists and the toy only goes 15 cm high. How much ENERGY was lost to air resistance? How much WORK was done by air resistance? What was the FORCE of air resistance during that 15 cm? (6 points) 2. Work A boat (mass = 500 kg or 5.00 x 102 kg) moves on the surface of the ocean, starting from rest, with three forces acting upon it: The wind blows with a force of 98 N at 40 South of west. The water exerts a drag force of 75 N to the east, and the motor can supply a force of 325 N to the North. As a result, the boat moves due North at a distance of 50.0 m. Assume that the weight of the boat is balanced by a buoyant force so there is no net force in the vertical direction. Your two dimensions are on the surface of the water. a) Draw the free body diagram for the boat. Your drawing should be a top view. That is north is up, south is down, etc. Don't worry about the vertical forces - they balance out (1 point) b) Which forces (if any) from part a) do positive work? Which (if any) do negative work? Which (if any) do NO work? (1 point) c) Find the amount of work done by each of the above forces (2 points) d) Find the net work done on the boat (1 point) e) Find the energy added or taken from the boat (1 point) f) What is the final speed of the boat? You can assume the boat starts from rest (4 points) A spring popper toy with a mass of 25 g is compressed by 35 mm. The spring constant is 100 N/m a) If no energy is lost, how fast will it be going when the spring is relaxed? (2 points) b) How high would it go if there were no air resistance? (2 points) c) In reality, air resistance exists and the toy only goes 15 cm high. How much ENERGY was lost to air resistance? How much WORK was done by air resistance? What was the FORCE of air resistance during that 15 cm? (6 points) 2. Work A boat (mass = 500 kg or 5.00 x 102 kg) moves on the surface of the ocean, starting from rest, with three forces acting upon it: The wind blows with a force of 98 N at 40 South of west. The water exerts a drag force of 75 N to the east, and the motor can supply a force of 325 N to the North. As a result, the boat moves due North at a distance of 50.0 m. Assume that the weight of the boat is balanced by a buoyant force so there is no net force in the vertical direction. Your two dimensions are on the surface of the water. a) Draw the free body diagram for the boat. Your drawing should be a top view. That is north is up, south is down, etc. Don't worry about the vertical forces - they balance out (1 point) b) Which forces (if any) from part a) do positive work? Which (if any) do negative work? Which (if any) do NO work? (1 point) c) Find the amount of work done by each of the above forces (2 points) d) Find the net work done on the boat (1 point) e) Find the energy added or taken from the boat (1 point) f) What is the final speed of the boat? You can assume the boat starts from rest (4 points)