A 3.00-kg object moves in a potential  U( x) =  A, where A is a positive constant. When the object is located at  x = -1.50 m, it has a kinetic energy (2.00 m) A. What is the range of the object's motion?   A)-2.00 m to +2.00 m B)-3.50 m to +3.50 m C)-10.5 m to +10.5 m D)-1.50 m to 1.50 m E)-0.50 m to +0.50 m

A man claiming a mountain carrying a bag with mass 7.5 kg , after 30 min he reach 8.2 m height from the start point. 1-calculate the work done from the man to the bag ? 2- if the man has weight 645 N , what is the work done while he carrying same bag ? 3-what is the energy difference between the man and the bag ?

7. A student in a lab exerts a 25 N force to pull a block a distance of 48 cm. If a total of 11 J of work is done, the angle between the force and the displacement is a. 89° b. 66° d. 24° e. none of the above c. 61° 8. A 102-g sparrow flying at 12.3 m/s wishes to have equal kinetic and gravitational potential energies. The height that will accomplish this is a. 0.315 m b. 0.628 m d. 1.13 m e. 7.72 m c. 0.787 m 9. Earth's mass is 5.98 x 1024 kg. Calculate the value of g at a point 4.8 x 105 km from the centre of Earth. a. 9.8 × 102 N/kg b. 8.3 x 10' N/kg C. 1.7 × 103 N/kg d. 1.7 x 10³ N/kg e. 9.8 × 105 N/kg 10. A piece of paper becomes electrically charged when a charged rod of plastic is placed close to it. This is referred to as a. charging by a conductor b. charging by induction c. charging by an insulator A P d. charging by contact e. charging by electricity 20 cm Ꭰ T 20 cm 11. Four charged spheres, A, D, P, and T are arranged as shown below. Sphere A has a charge of +4.5 × 10*C,…

If an object of mass 2.00 kg is dropped from rest into free fall from some height where it has +5.00 Joules of gravitational potential energy, then what kinetic energy will it have when its height is zero?   a. 5.00 J   b. 4.00 J   c. 10.0 J   d. 2.00 J   e. zero J

9- How much work must be done to stop an 1800 kg vehicle traveling at 30 m/s ? a- 1.8 x 104 J b- 5.4 x 10*j C- 5.3 x 105 J d- 8.1 x105 J

Work: A force F(x,y) = 12 N i- 10 N j acts on an object. How much work does this force do as the object moves from the origin to the point r(x,y) = 13m i+ 11m j.

1. A roller-coaster car with a mass of 1200 kg starts at rest from a point 20 m above the ground. At point B, it is 9 m above the ground. [Express your answers in kilojoules (kJ).] a. What is the initial potential energy of the car? b. What is the potential energy at point B? c. If the initial kinetic energy was zero and the work done against friction between the starting point and point B is 40 000 J (40 kJ), what is the kinetic energy of the car at point B 2. The time required for one complete cycle of a mass oscillating at the end of a spring is 0.80 s. What is the frequency of oscillation?

1480 kg car accelerates uniformly from a position of rest to a speed of 95 km/h in 6.0 s. a) Calculate the car's acceleration. b) How far did the car travel during this acceleration?  b) How much work was done by the car during this 6.0 s?

An object with a mass of 15kg slides down an incline with a length of 6.0m at an angle of 28 degrees from horizontal.  The coefficient of friction between the object and incline is 0.25  a) How much work does the gravitational force perform on the object? b) How much work does the frictional force perform on the object?  c) What will its speed be as it reaches the bottom of the incline?

Q 3. Three cars are traveling at 30km/h, 50km/h and 200km/h, respectively. Each speed corresponds to a certain kinetic energy. a)  Note down the expression for the kinetic energy of a moving object with a velocity v. b)  Note down the potential energy for an object lifted up from the ground to height h. c)  Based on a) and b) find an expression for the height as a function of velocity by assuming that the kinetic energy equals the potential energy of the same object. In other words find h(v) from which the object would need to be dropped and calculate the height so it has a speed of 30 km/h, 50 km/h or 200 km/h on impact with the ground. Assume free fall without air resistance d)  Comment on your chances of survival if you are involved in head-on collisions for the three different speeds.