Showing 211 to 220 of 400 Questions
  • Two ice skaters, Daniel (mass 65.0 kg) and Rebecca (mass 45.0 kg), are practicing. Daniel stops to tie his shoelace and, while at rest, is struck by Rebecca, who is moving at 13.0 m/s before she collides with him. After the collision, Rebecca bas a velocity of magnitude 8.00 m/s at an angle of 53.1" from her initial direction. Both skater

  • An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. But she does have devices to measure distance and time accurately. She knows her own mass is 78.4 kg, but she is unsure of the mass of a large gas canister in the airless rocket. When this canister is approaching her at 3.50 m/s, she pushes a

  • Changing Mass An open-topped freight car with mass 24,000 kg is coasting without friction along a level track. It is raining very hard, and the rain is falling vertically downward. Originally, the car is empty and moving with a speed of 4.00 m/s. What is the speed of the car after it has collected 3000 kg of rainwater?

  • Asteroid Collision Two asteroids of equal mass in the asteroid belt between Mars and Jupiter collide with a glancing blow. Asteroid A, which was initially traveling at 40.0 m/s, is deflected 30.0" from its original direction, while asteroid B travels at 45.0 to the original direction of A (Fig. 8.36). (a) Find the speed of each asteroid

  • A 15.0-kg fish swimming at 1.10 m/s suddenly gobbles up a 4.50-kg fish that is initially stationary. Neglect any drag effects of the water. (a) Find the speed of the large fish just after it eats the small one. (b) How much mechanical energy was dissipated during this meal?

  • Two fun-loving otters are sliding toward each other on a muddy (and hence Iiictioo1ess) horizontal surface. One of them, of mass kg, is sliding to the left at 5.00 m/s, while the other, of mass 5.75 kg, is slipping to the right at 6.00 m/s. They hold fast to each other after they collide. (a) Find 1he magnitude and direction of the

  • Deep Impact Mission in July 2005, NASA's "Deep Impact" mission crashed a 372-kg probe directly onto 1he surface of the comet Tempell, hitting the surface at 37,000 km/h. The original speed of the comet at that time was about 40,000 km/h, and its mass was estimated to be in the range (0.10-2.5) X lO14 kg. Use the smallest value of the esti

  • A 1050-kg sports car is moving westbound a11S.0 m/s on a level road when it collides with a 632O-kg truck driving east on the same road at 10.0 m/s. The two vehicles remain locked together after 1he collision. (a) What is the velocity (magnitude and direction) of 1he two vehicles just after 1he collision? (b) At what speed should the

  • On a very muddy football field, a 110-kg linebacker tackles an 85-kg halfback. Immediately before the collision, the linebacker is slipping with a velocity of 8.8 m/s north and the halfback is sliding with a velocity of 7.2 m/s east. What is the velocity (magnitude and direction) a1 which the two players move toge1her immediately after th

  • Two skaters collide and grab on to each other on flectionless ice. One of them, of mass 70.0 kg, is moving to the right at 200 m/s, while the other, of mass 65.0 kg, is moving to the left at 2.5O m/s. What are the magnitude and direction of the velocity of these skaters just after they collide?