Answer:
Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work).
Explanation:
It is a measure of how well a machine reduces friction.
Answer:

Explanation:
you mean deceleration right ? because the acceleration is 250m/s
Astronomers find white dwarfs that distinguish them from main sequence stars because white dwarfs get really hot, we can search for their ultraviolet radiation.
<h3>What is a white dwarf?</h3>
A white dwarf is a very hot star that radiated much energy in the form of ultraviolet radiation.
This UV radiation is initially very bright and then these stars become red with time.
In conclusion, Astronomers find white dwarfs they can search for their ultraviolet radiation.
Learn more about white dwarfs here:
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