Physics Question
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A question for physics
need quick answer
Q.A truck of mass 2500 kg moving along a straight, level road. The engine enables a forward force of 12000 N to act on the truck. There are also counter forces that total 3200 N acting against the truck. As the truck goes faster with the same forward force, its acceleration becomes less. Eventually, the truck travels at a constant speed. Explain why this happens.
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Give you a tip: Because the resultant force = 0. Which means the forward force is equal to the backward force.
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but how the truck will have less acceleration nd then without even changing the forward force the truck has constant speed...???
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Zero acceleration does not mean zero velocity. Acceleration comes into play when reducing/increasing velocity.
As it goes faster, more force is required to overcome the frictional forces acting against it, hence after a given time/speed, all the forward force is used to maintain the truck's speed, since no extra forces is available to provide acceleration.
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It implies that the counter forces increase while the speed increases. The acceleration will be reduced to 0 when the counter forces increases to 12000N. The truck thereafter will travel at a constant speed and the counter forces will stay at 12000N to give a zero net force.
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The counter force 3200N that the truck experienced is frictional force. There is another type of counter force which is air resistance that increases as the speed of the truck increases. Hence the resultant force decreases unitl it become zero when the net counter force ( frictional + air resistance) equals the magnitude of the forward engine force. According to Newton's 2nd Law, the accerelation is now zero and the truck travels at its constant maximum velocity known as terminal velocity.
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thnx to alll of u... i got the answer already...