111. 222. b) 444. 555. 666. An electric stove has a power rating of 1.0 kW on its large burner. If the stove heats 2.3 L of water for 10 minutes from 10C to 65C, how much energy is lost to the environment? Assume that water requires 4.2 x 103 J/(CL). Tarzan runs up a flight of stairs to a height of 13.0 m above his starting point in 18.0 5. If his mass is 83.0 kg, what is his average power? what is the total amount of energy transferred? A slingshot with a spring constant of 200 N/m is pulled hack 8.0 cm. A 20 g pea is launched by the slingshot horizontally. At what speed does the pea leave the slingshot? The bumper of a 2000 kg car has a spring constant of 5 x 106 N/m. The car is moving at 4.5 m/s horizontally when it crashes into a solid brick wall. How much will the car's bumper be compressed if the car comes to a complete stop? A 1.2 kg spring laboratory cart is held against a wall. The spring constant is 65.0 N/m. The spring is compressed 8.0 cm when heid against the wall. What is the compression of the spring when the cart's velocity is 42.0 cm/s? A 500 g hockey puck is travelling head-on at 33.0 m/s toward a goalie's pads. The goalie, initially at rest and completely padded, has a mass of 75.0 kg. The puck causes the goalie's pad to be compressed by 3.00 cm and pushes her backward at 0.300 m/s. Calculate the momentum and kinetic energy of the puck and the goalie before collision. Calculate the velocity of the puck after collision. Calculate the kinetic energy ofthe puck and the goalie after collision. Is this collision elastic or inelastic? Explain. An elastic collision occurs between a 10 g marble and a 50 g marble. The smaller marble is travelling north at 5.0 m/s in a head-on collision course with the other marble, initialiy at rest. Determine the final velocities of both marbles. 5. Two metal gliders are floating along a horizontal air track and collide elastically. The first glider 200 g is moving at 32.0 cm/s while the second glider 300 g is moving in the opposite direction at 52.0 cm/s. What is the velocity of each glider after impact? 2. What is the effective value of 'g' 1000 km above Earth's surface? Earth has a mass of 5.98 x 1024 kg and a radius of 6.38 x 106 m. 3. A 1000 kg rocket fired from Earth has a speed of 6.0 km/s when it reaches a height of 1000 km above Earth's surface. al If the rocket has used all of its fuel, will it escape from Earth? b) If it does not escape, what maximum height above Earth will it reach? Answer Key: 2. 7.32 m/s2 3a) No b) 4.7 x 106 m 22. Given mjupitef = 1.9000 x 1027 kg and gunner = 7.1500 x 10? m, what would be the escape speed of an object 10 000 km above Jupiter's surface? 33a) How much speed would have to be added to the Moon for it to leave Earth's influence? Given r = 3.82x103m, mM = 7.35x10\" kg, m = 5.98x1024 kg . Earth to Moon oon Earth b) How much energy would it take to achieve your answer in 3}? Answer Key: 22. 55767 m/s 33a) 423 m/s b} 3.84 x 10sz 13. If a 100 000 kg shuttle enters Earth's atmosphere at 4.0000 km/s and lands at 80.000 m/s, how much energy has it released to the atmosphere? 14. A 920 kg satellite is projected vertically upward from Earth's surface with an initial kinetic energy of 7.00 x 109J. Find a) its maximum height. b) the initial kinetic energy it would have needed to keep going indefinitely. c) the initial speed it would have needed to keep going indefinitely. 15. 550 kg satellite projected upward from Earth's surface reaches a maximum height of 6000 km. Find a} its change in gravitational potential energy. b) its initial kinetic energy. 16. A 20 000 kg meteorite from outer space is headed directlyr toward Earth with a speed of 3.0 km/s. Find its speed when it is 200 km above Earth's surface. 17. The escape speed at the event horizon of a black hole is defined as the speed of light, c. What would the size of Earth have to be for it to be compressed to a black hole? (Le. Find the radius of the Earth. Use 3.00 x 108 m/s as the speed of light) 18. At what location from Earth are the gravitational fields of Earth and the Moon balanced? Given r = 3.82x1o8 m, mM 2 7.3.5x1022 kg, m = 5.98x1024 kg Earth to Moon oon Earth 20. Find the speed of an Earth satellite in orbit 400 km above Earth's surface. What is the period ofthe orbit