A machine can never be 100% efficient because some work is always lost
due to the lack of materials or equipment that would convert work by 100%. It follows
the second law of entropy. The ideal engine is known as Carnot’s engine having
a 100% efficiency. So far, no engine has ever gotten to 100%.
Answer:
height from where rock was thrown is 27.916 m
Explanation:
speed = 7.50 m/s
θ = 30°
g= 9.8 m/s²
horizontal distance = 18 m
time require for vertical displacement

t = 2.8 sec
now for calculation of height
s = ut + 0.5 a t²
-h = v sinθ× t + 0.5 ×(-9.8)× (2.8²)
-h = 7.5 sin30°× 2.8 - 0.5 ×(9.8)× (2.8²)
-h = -27.916 m
h= 27.916 m
height from where rock was thrown is 27.916 m
Answer: 2.83 minutes
Explanation:
It is understood that trains are approaching. That is, they have speeds of equal magnitude but opposite. When train A travels x meters northbound, then train B travels the same distance southbound.
Therefore trains approach at a speed of:

Then:

Where x is the distance between the trains

So the time in which both trains meet is:

This is:

<em />
<em>How long will it be before they reach one another ?</em>
<h3>2.83 minutes</h3>
Individuals suffering from somatoform disorders often see several doctors about their symptoms because doctors often refer their patients for a second opinion
<h3>What is doctors opinion?</h3>
Doctors usually ask people to take different medications to be able to treat the cause and the symptoms of a disease.
For example, they might prescribe antibiotics to treat the infection and anti-inflammatory medication for the swelling and pain.
According to this, the statement that says that doctors often advise a combination of treatments to eradicate an infection and treat symptoms is true.
Hence Individuals suffering from somatoform disorders often see several doctors about their symptoms because doctors often refer their patients for a second opinion
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