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← 10x-14 Pushing a Car

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Showing Revision 1 created 10/27/2012 by Amara Bot.

  1. If you happen to drive a car with a manual transmission
  2. and you've ever let the battery die, well, there's a good chance you've had to push your car.
  3. Let's talk about the forces involve in pushing a car.
  4. Let's say we're lucky enough to have 3 people pushing this car.
  5. Our green- and purple-haired doctors and, oh I don't know, Albert Einstein.
  6. Let's say we're looking at this car from above.
  7. Here's our bird's-eye view of the car--from above--and the mass of this car is 1000 kg.
  8. Let's say Einstein is pushing from directly behind--here's the top of Einstein's head,
  9. and there are his arms.
  10. The green-haired doctor is pushing from the side at a small angle, you'll notice.
  11. The purple-haired doctor is pushing from the other side, also at a small angle.
  12. Let's say an interesting fact about this group of friends
  13. is that they can all push with exactly the same force.
  14. When they all push on this car at that same time with this exact same force,
  15. the acceleration of the car is 0.5 m/s².
  16. The angle that the green- and purple-haired doctors are pushing at we'll call α.
  17. For this problem α is 30 degrees, so they're pushing at a 30-degree angle.
  18. Einstein here is pushing directly up on the back of the car,
  19. but these guys are doing it at a 30-degree angle.
  20. I want you to tell me with what force is each person pushing.
  21. Enter your answer here in Newtons.