Friction Paradox: The Mystery of Constant Speed Motion

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    Friction Paradox
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The discussion centers on the friction paradox, where a block moves at constant speed with balanced external force and friction. It highlights the confusion about energy requirements when changing frames of reference. While the block appears at rest to an observer running alongside it, energy is still being expended to maintain motion relative to the ground. The key point is that energy is always required to overcome friction, regardless of the observer's frame of reference. Thus, changing perspective does not eliminate the need for energy input in the system.
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I was reading this book on mechanics by derek raine and came up on something called friction paraddox.
Suppose a block is is moving with constant speed and the external force is balanced by friction. We know friction causes heat dissipation and the external force supplies some energy so as to keep the speed constant.suppose I run along with the block at same speed and with respect to me, block is in rest and there is no heat dissipation. So how come I have beem able to remove the need for supplying energy just by changing my frame of reference? Thanks in advance!
 
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VVS2000 said:
So how come I have beem able to remove the need for supplying energy just by changing my frame of reference?
You haven't. In your frame of reference you are expending energy to move the floor under you.
 
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