Basic Forces- Just seeking a simple answer

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To lift a car with a mass of 1000 kg at a constant speed in a gravitational field of 10 N/kg, a force of 10,000 N is required. This force balances the weight of the car, calculated using W = mg. The discussion clarifies that since the car is lifted at constant speed, there is no net force acting on it, as acceleration is zero. Participants emphasize that the upward and downward forces are equal at 10,000 N, resulting in no net force. The conversation highlights the importance of understanding balanced forces in this context.
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Homework Statement



Given that the mass of a car is 1000kg, gravitational field strength = 10N/kg

Find the force required to just lift the book up at a constant speed.


The Attempt at a Solution



Constant speed, Accel. = 0

W = mg
= 1000kg * 10N/kg
= 10,000N

Therefore force needed to just lift the book is 10,000N?

However, by the Newton's law, in balanced forces, object at rest will remain at rest... So the car was originally at rest, will it be lifted up by 10,000N?
 
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is it book or car? .. can you please clarify your question..
 
thebigstar25 said:
is it book or car? .. can you please clarify your question..

sorry, its a car
 
your answer is correct .. And regarding your last question, i believe that as long as the car is lifted at constant speed we can not say that there is a net force upward, since if a=0 this implies F=ma=0 N .. What we can say is that we have two forces one upward and the other downward with a value of 10,000N.. When you say it is lifted up with 10,000N it is as you are saying that the net force is 10,000N upward ..

Im not sure whether the other members would agree with my point, but I believe it is that way ..
 

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