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Physics/Acceleration of Moving Objects.

Question
Does it take more force to accelerate a moving object?   An example would be a long truck that has a safe in the back. As the truck starts accelerating from 0 to 60 MPH,  the safe is moved from the back to the front at a constant  speed.  Would it take more force to accelerate the truck if the safe were moving!?

The rate of acceleration of an object is NOT dependent on the object's current velocity. It only depends on the magnitude ofthe force being applied, the direction of that force and the mass of the object being accelerated; all of which is incorporated into Newron's 2nd Law of motion.
F=m*a
And no, if the safe is being moved within the truck bed at a constant speed (relative to the truck) there would be no effect on the rate of acceleration of the truck. As long as the safe is being moved at a constant speed the rate of acceleration of the truck would remain the same.

Physics

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James J. Kovalcin

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I am teaching or have taught AP physics B and C [calculus based mechanics & electricity and magnetism] as well as Lab Physics for college bound students. I have a BS in Physics from the University of Pittsburgh and a Master of Arts in Teaching from same. I have been teaching physics for 34 years. I am constantly updating my skills and have a particular interest in modern physics topics.