Imagine a car crash. A car coming at a high speed has a head on collision with a car at rest. When the car makes impact, it will move the other car with it at a slower speed then it was travelling at. In this case, the velocity decreased since the car slowed down, but the mass increased since there are now two cars moving. Momentum was conserved because the change in mass accounts for the loss of velocity.
The coefficient of kinetic friction (μ) between the block and the table is 0.4.
<h3>
What is kinetic friction?</h3>
This sis the frictional force between an object in motion with the surface in contact.
μN = ff
where;
- N is normal reaction due to weight of the block
- ff is frictional force
- μ is coefficient of friction
μ = ff/N
μ = 8/20
μ = 0.4
Thus, the coefficient of kinetic friction (μ) between the block and the table is 0.4.
Learn more about coefficient of friction here: brainly.com/question/20241845
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charge = current x time = 0.5x 20=10Coulombs
Answer:
Explanation:
According to the law of conservation of linear momentum, the total momentum of both pucks won't be changed regardless of their interaction if no external forces are acting on the system.
Being 
and 
the masses of pucks a and b respectively, the initial momentum of the system is
Since b is initially at rest
After the collision and being 
and 
the respective velocities, the total momentum is
Both momentums are equal, thus
Solving for 
The initial kinetic energy can be found as (provided puck b is at rest)
The final kinetic energy is
The change of kinetic energy is
