7. The neighbor who pushes the lawnmower four times as far but exerts only half the force does more work. Work is calculated by multiplying force by distance. Therefore, if the neighbor pushes the lawnmower four times as far but exerts only half the force, they are doing (4 x 2) = 8 times more work than you.
8. To find the mass of the car, we can use the formula for kinetic energy: KE = 0.5 * mass * velocity^2. Plugging in the values given, we get:
5040000 J = 0.5 * mass * (60 m/s)^2
5040000 J = 0.5 * mass * 3600 m^2/s^2
5040000 J = 1800 * mass
mass = 5040000 J / 1800 = 2800 kg
Therefore, the mass of the car is 2800 kg.
9. To find the speed of the ball, we can use the formula for kinetic energy: KE = 0.5 * mass * velocity^2. Plugging in the values given, we get:
98 J = 0.5 * 4 kg * velocity^2
98 J = 2 * velocity^2
velocity^2 = 98 J / 2 kg = 49 m^2/s^2
velocity = sqrt(49) m/s = 7 m/s
Therefore, the ball is rolling at a speed of 7 m/s.
3. If a neighbor pushes a lawnmower four times as far as you do but exerts only half the force, which one of you does more work and by how much? 4. A 0.075 kg ball in a kinetic sculpture moves at a constant speed along a motorized vertical conveyor belt. The ball rises 1.32 m above the ground. A constant frictional force of 0.35 N acts in the direction opposite the conveyor belt’s motion. What is the net work done on the ball?
2 j/0.18 x 9.8 m/s = 1.13
loading...
8. Find the mass of a car that is traveling at a velocity of 60 m/s North. The car has 5,040,000 J of kinetic energy. 9. How fast is a ball rolling if it contains 98 J of kinetic energy and has a mass of 4 kg
1 answer