If a car engine provides 800N of force and the car is moving at constant velocity,
i. Does the air resistance acting on the car have a magnitude of 800N? If so, is the magnitude of the air resistance proportional to the force provided by the engine?
ii. Are the forces, the one provide by the engine and the air resistance, a pair of
action and reaction pair?
P.S. Not homework.
Air resistance
2013-05-31 9:15 pm
回答 (2)
2013-06-01 12:12 am
✔ 最佳答案
(i) If you neglect friction on the tyres, the air resistance force is balanced by the force delivered by the engine.In general, air resistance is proportional to the speed of a given object moving at low speed. At high speed, air resistance is proportional to the square of speed. The situation becomes more complicated if turbulence exists.
(ii) No, they are NOT action and reaction pair.
When the car moves forward, it tends to drag along the surrounding air to move forward together. This is the action force and which acts on the air. The reaction force, which acts on the car by the air becomes the air resistance.
2013-05-31 9:59 pm
當然唔係啦，除非空氣和地面密度係相同。
收錄日期: 2021-04-29 17:52:40
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