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The friction force multiplied by the displacement of the plank below is equal to the change in kinetic energy of the plank below;

The friction multiplied by the displacement of the wood block above is equal to the reduction of kinetic energy of the wood block above;

The displacement of the upper wooden block is greater than the displacement of the lower wooden block (because the velocity of the upper block is large, otherwise there would be no relative motion and friction), so the kinetic energy of the upper wooden block decreases more than the kinetic energy of the lower wooden plank, and this part of the energy difference is what you call the heat generated by friction.

In other words: heat generated by friction = friction * relative displacement between the upper and lower plates.

The amount of kinetic energy change of the plank is the work done by the resultant force, i.e., the frictional force experienced by the plank multiplied by the displacement of the plank.

The work done by a wooden block is the frictional force multiplied by its displacement relative to the ground. This is where the heat generated by friction is involved.

For the wood below, use the "kinetic energy theorem", that is, in the formula f*l=δek, L is the displacement of the plank, and δek is the change in the kinetic energy of the plank) The "heat" generated by the frictional force is equal to the "frictional force" multiplied by the "relative displacement", which is for the system. q=f*l'

where l'is the displacement of the block relative to the board).

In the horizontal direction, the woodblock is subject to friction, and the heat generated by friction is also converted by this part of kinetic energy. And this is the ideal state, and the heat generated by friction should be ignored.

Hehe. The reason for this problem is that you don't understand friction enough.

Let's say the length of the plank below is l

Then, when the force is analyzed, the kinetic energy change of the lower wooden board is fs, and the kinetic energy change of the upper wooden block is f(l+s).

There's a difference fs here

This is frictional heat generation.

Frictional heat generation looks at the relative displacement.

I see.

Kinetic energy and heat produced by friction have nothing to do ......

The change of kinetic energy is related to the force and time of action, and has nothing to do with the transformation of energy......The object above ......It's hard to say......

There is a displacement difference between the upper and lower boards, that is, the active power difference.

1kj=1000j 1k=℃+

1j= 1℃=

Take it directly to the unit.

1. A skydiver weighs 600N, the total weight of his parachuting equipment is 200N, and the air resistance he receives in the process of falling at a constant speed in the air is 800 N.

Uniform motion, two forces are balanced, resistance = gravity.

2. Tie an object weighing 500N to the wire rope, when the wire rope pulls it up at a constant speed, the rope pulls the object at a constant speed of 500 N, when the steel rope pulls the object to rest, the rope pulls the object at a constant speed of 500 N, and when the rope pulls the object at a constant speed of 2m s, the rope pulls the force on the object is 500 N.

Constant motion and rest, two forces are balanced, resistance = gravity.

Physical wolf pack.

n

n，500n，500n

There is no why, the cow must be lawful!