Please solve all of 4 1. A 0.63 kg ball is thrown upwards with an initial speed of 14 m/s and reaches a maximum height of 8.1 m. Howmuchis dissipated by the air drag on the ball during its ascent.energyAnswer: 11,7J2. A 0.55 kg projectile is launched from the edge of a cliff with an initial kinetic energy of 1550 J. The highest pointit reaches above the launch point is 140m.a) What is the horizontal component of its velocity?b) What was the vertical component of its velocity just after launch?c) At one instant during its flight, the vertical component of the velocity is 65 m/s. At that time, how far is itabove or below the launch point?Answers: a) 54 m/sb) 52 m/s c) 76 m below the launch height3. A skydiver of mass 68 kg falls at a constant terminal speed of 59 m/s.a) At what rate is the gravitational potential energy of the Earth-skydiver system being reduced?b) At what rate is mechanical energy being dissipated?Answers: a) 3.9×10 Wb) 3.9x104 W4. A pendulum is made of a 2.0 kg stone swinging on a 4.0 m string of negligible mass. The stone has a speed of 8.0m/s when it passes its lowest point.a) What is the speed when the string makes an angle of 60°to the vertical?b) What is the greatest angle with the vertical the string will make during the stone's motion?c) If the potential energy of the pendulum-Earth system is taken to be zero at the stone's lowest point, what isthe total mechanical energy of the system?Answers: a) 5.0m/s b) 79° c) 64.0J

Answered: Image /qna-images/answer/232c1432-7722-4f6a-9d5e-c9cec3e1ab34.jpg

4. A pendulum is made of a 2.0 kg stone swinging on a 4.0 m string of negligible mass. The stone has a speed of 8.0 m/s when it passes its lowest point. a) What is the speed when the string makes an angle of 60°to the vertical? b) What is the greatest angle with the vertical the string will make during the stone's motion? c) If the potential energy of the pendulum-Earth system is taken to be zero at the stone's lowest point, what is the total mechanical energy of the system? Answers: a) 5.0 m/s b) 79° c) 64.0J

4. A pendulum is made of a 2.0 kg stone swinging on a 4.0 m string of negligible mass. The stone has a speed of 8.0 m/s when it passes its lowest point. a) What is the speed when the string makes an angle of 60°to the vertical? b) What is the greatest angle with the vertical the string will make during the stone's motion? c) If the potential energy of the pendulum-Earth system is taken to be zero at the stone's lowest point, what is the total mechanical energy of the system? Answers: a) 5.0 m/s b) 79° c) 64.0J

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter7: Work, Energy, And Energy Resources

Section: Chapter Questions

Problem 21PE: In a downhill ski race, surprisingly, little advantage is gained by getting a running start. (This...

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