<u>Yes, work is done when a book falls of the table.</u>
This is because:
When the book falls, it's potential energy is converted into kinetic energy. As it reaches the floor down, this kinetic energy is converted to heat energy and sound energy due to the impact.
When a force is imposed on an object to cause displacement of that object, work is done on that object. For a force to do work on an object, there should be a displacement and this force should cause the displacement. So here, since the book falls from the table and causes the displacement of the book from the table to the floor. It is said that work is done.
Work can be given by the formula:
W = F • d
where F is the force and d is the displacement.
B. By vibrations in wires or strings
When designing tires for a car, an engineer must consider the materials that will be used to fabricate the tires ... both the suitability of the materials for the purpose, and their cost.
For example, the engineer should not design car tires to be made of glass or of silk, since these would not hold up well when driving on concrete roads, and they would need to be replaced too often.
For another example, he should not design car tires to be made of gold or polished diamond, since these would be beyond the price range of most car owners, and also, these tires would be very susceptible to being stolen by nefarious and dishonest individuals in the middle of the night.
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I hope this answer is helpful. The question you posted is a very difficult one, because there are no answer choices listed, and also because the question has the mysterious unknown term "the following" in it.
Answer:
Yes
Explanation:
Since velocity is a vector, meaning it also relies on direction, the average speed can be different from her average velocity. An example would be if a runner turned around and ran backward after running 10 meters and returned to her starting point. If you took her average velocity of the entire trip it would actually be 0 but her average speed obviously would not be. This is why velocity can be negative but speed cannot.
Answer:
The speed when se reaches the top of the incline is 0.28 m/s
Explanation:
The work done is equal to the change of kinetic energy, then:
Wg + Wf + Wn = ΔEk
Where
Wg = work done by gravity
Wf = work done by force
Wn = work done by normal force

Where
m = 8.5 kg
g = 9.8 m/s²
d = 39.93 m
F = 37.4 N
vf = 2 m/s
Replacing:
