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

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Q: 6. You notice that an object is moving from point A to point B. The object measures a kinetic energy…

A: Given data: The kinetic energy at A is KE=6.75 J. The speed at A is vA=4.25 m/s. The speed at B is…

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A: Here Mass of a box = 18kg released from rest on a rough inclined plane and slides to the bottom.…

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A: Given data: The mass of crate is m=60.1 kg. The rise in crate is h=3.62 m.

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Q: You lift a 1 kg object from the floor to the top of a 1.5 m high table. 1. What is the force needed…

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Q: A 200-kg box is lifted by a forklift from the ground to a height of 2.0 m. i. What is the work done…

A: i. work done by the forklift is W=mgh=200 kg9.8 m/s22 m=3800 J

Q: 10. A person jumped into the ocean from a car which was 320 m above the water's surface. He had a…

A: Given: mass of person, m = 94 kg  Initial height of person, h1 = 320 m final height, h2 = 75 m

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A: We are given weight of person. We are also given the height of mountain. The work done is the…

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Q: 1. A 6.2kg box is moving at 2.4m/s to the left. a) What is its kinetic energy? 2.4m/s 6.2kg b) How…

A: Given data:  Mass (m) = 6.2 kg Initial velocity (u) = 2.4 m/s Work done by the friction (W) = -4 J…

Q: A 0.60 kg rubber ball is thrown into the air. At a height of 30 m above the ground, it is travelling…

A: Given: Mass,m=0.60kgAcceleration due to gravity,g=9.8m/s2Height,h=30mVelocity,v=18m/s An object's…

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Q: 2. A 10-kg mass is dragged on a horizontal frictionless surface by a force F(x) = 2x + 1 (N) that…

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Q: 3. A 60.0-kg skier is at top of a slope. At the initial point, she is 10 m vertically above point A.…

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Q: 50 - meter rope with a mass of 30 kg is dangling over the edge of a cliff. Ignoring friction, how…

A: Mass (m) = 30 kgLength of rope (L) = 50 m

Q: A 5.5 kg bird is flying 12 m above the ground. What is the Potential energy of the bird is…

A: Mass of bird (m) = 5.5 kg Height of bird above ground (h) = 12 m g = 9.8 ms2

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Q: Suppose you lift a 20 kg box by a height of 1.0 m.a. How much work do you do in lifting the box?…

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Q: A force F(x) = (-5.0x² + 8.0x) N acts on a particle. a. How much work does the force do on the…

A: The force act on a particle, Fx=-5.0 x2+8.0 x N   The work done in moving the particle from x=2.0 m…

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A: (a) The work done in lifting the box is

Q: Answer the following questions: a. If you push a lawn mower across a yard in 10 seconds, how does…

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Q: 3 meters above the base.

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Q: A 70-kg hiker hikes from an elevation of 1,209 m to an elevation 2,199 m. i. What is the hiker’s…

A: i) As the hiker moves from a lower elevation to a higher one the gravitational potential energy of…

Instantaneous Power

Power is defined in physics as the amount of energy transmitted or transformed per unit time. The watt is the unit of electricity in the International System of Units, equivalent to one joule per second.