Q.8 How much work is needed to stop a 2540 kg car that is moving straight down the highway at 25 km/h?

Karen and Randy are playing with a toy car and track. They set up the track on the floor as shown in the figure below, where the apparatus on the far left is used to launch the car forward by pressing down on the top portion. After the car is launched, it follows the track and continues upward, leaving the track. If the car has a mass of 127 g and it reaches a maximum vertical height of 2.90 m above the floor, what was the speed of the car while it was moving along the floor? Ignore the effects of friction and air resistance. m/s

Q5; A 0.37-kg particle has a speed of 4.0 m/s at point A and kinetic energy of 8.2 J at point B. (a) What is its kinetic energy at A?  J(b) What is its speed at point B? Your response differs from the correct answer by more than 10%. Double check your calculations. m/s(c) What is the total work done on the particle as it moves from A to B? J

A woman runs up a flight of stairs. The gain in her gravitational potential energy is 1000 J. If she runs up the same stairs at half the speed, her gain in gravitational potential energy will be . . .  Group of answer choices 500 J 2000 J 100 J 1000 J

The two masses in the figure are released from rest. After the 3.0-kg mass has fallen 1.5 m, it is moving with a speed of 3.8 m/s. How much work is done during this time interval by the frictional force on the 2.0 kg mass? 2.0 kg 3.0 kg O-20 J -28 J -8.0 J O-17 J 0-12 J

The driver of a 760.0 kg car decides to double the speed from 21.1 m/s to 42.2 m/s. What effect would this have on the amount of work required to stop the car, that is, on the kinetic energy of the car? KE x 105 J KE = × 105 J (select) v times as much work must be done to stop the car.

1. A 1000 kg car is driving forward with a speed of 25 m/s. It comes to rest in a distance of 100m. a) What is its change in kinetic energy during this process? ANSWER: b) What was the magnitude of the net force needed to bring the car to rest over that distance? ANSWER:

4. A 2.5 kg object falls vertically downward in a viscous medium at a constant speed of 2.5m/s. How much work is done by the force the viscous medium exerts on the object as it falls 80.0cm? A. -2.0 x 10 J B. -39 J C. 39 J D. 2.0 × 10 J E. O J

DETAILS SERPSE10 7.8.P.035.MI. (a) the work done by this force on the particle 1 A single conservative force acts on a 5.30-kg particle within a system due to its interaction with the rest of the system. The equation F, 2x + 4 describes the force, where F, is in newtons and is n meters. As the particle moves along the x axis from x 1.02 m tox-6.20 m, calculate the following (b) the change in the potential energy of the system (c) the kinetic energy the particle has at x 6.20 m if its speed is 3.00 m/s at x 1.02 m 3 Need Help? MY NOTES Pa ASK YOUR TEACHER PRACTICE ANOTHER