A .25 kg volleyball is dropped out of a window that is 25 m above the ground. The ball is caught by a net placed on the ground. A) how much work is done on the ball by its weight? What is the gravitational potential energy of the basketball, relative to the ground, B) when it is released from the window and C) caught on the ground

Someone drops a 70 – g pebble off of a docked cruise ship, 50.0 m from the water line. A person on a dock 5.0 m from the water line holds out a net to catch the pebble. (a) How much work is done on the pebble by gravity during the drop? (b) What is the change in the gravitational potential energy during the drop? If the gravitational potential energy is zero at the water line, what is the gravitational potential energy (c) when the pebble is dropped? (d) When it reaches the net? What if the gravitational potential energy was 40.0 Joules at water level? (e) Find the answers to the same questions in (c) and (d). |

1. A Roller Coaster showing in the picture bellow of mass of M=149 Kg is moving through the 3 hills until the end of the rid. if the first hill has Hight of H1=24 m, the second hill H2 = 17 m and the Third hill H3= 12 m. calculate the following: First hill M Scale 1.0 cm 3.0 m Second hill hill ⠀⠀ End of ride a) Potential energy at the maximum height (first hill) in (J) : b) The Kinetic Energy in the second hill :: c) the velocity of the car in the third hill :: d) The velocity of the car at the end of the rid (e) Kinetic energy at the end of the hall (J) :

6. For vectors B = -î – 4ĵ and Å = -31 – 2j, calculate: a. Ā +B and its magnitude and direction angle b. A-B and its magnitude and direction angle.

A 1200 kg roller coaster car starts at point A, then travels 165 ft at 40.0° below the horizontal to point B. (a) Taking point B to be the level where the gravitational potential energy of the car-Earth system is zero, what is the potential energy (in J) of the system when the car is at points A and B, and the change in potential energy (in J) as the coaster moves between these points? at point A at point B change in potential energy J (b) Repeat part (a), setting the zero configuration with the car at point A. at point A J at point B J change in potential energy J

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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,…

A 0.25 kg volleyball is dropped out of a window that is 25m above the ground the ball is caught by a net placed on the ground A ) how much work is done on the ball by it’s weight ? B) what is the gravitational potential energy of the basketball relative to the ground & when it is released from the window and caught at the ground ??

The top of a descending ski slope is 50 m higher than the bottom of the slope. A 60-kg skier starts from rest and skis straight to the bottom of the slope. If 20% of the gravitational potential energy change of the skier  is converted into internal energy (due to friction and air drag), how fast is the 60-kg skier traveling at the bottom of the slope? Again, represent the process with work-energy bar charts indicating the system, the initial state, and the final state.

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