Answer: temperature of the hot reservoir is 303.52K
Explanation:
Th=temperagture of hot reservoir
Tc=temperature of cold reservoir 263K
Eff=efficiency of the refrigerator
Cop=coefficient of performance
7
Eff=1/cop
Eff=1/7
Eff=0.142
Eff=1-263/th
0.142-1=-263/th
-0.858=-263/th
Th=303.52K
<h2>
So, the correct answers are:</h2>
Travels in longitudinal waves
Travels most slowly through a gas
Speeds up when temperature is increased
Is caused by vibration
Explanation for correct answers:
Yes, it does travel in longitudinal waves
Yes, sounds weird, but travels faster in the water
Yes, does speed up when temperature is increased
And yes, Is caused by vibration.
<h2>
Wrong answer is:</h2>
Can travel through a vacuum
Explanation for wrong answer:
actually, in space, there is NO sound, because there are no particals for the sound to vibrate with, there's just empty SPACE.
Momentum = Mass x Velocity
Put the values where they belong and solve for Velocity.
In this case, since Mass is being multiplied by Velocity, to solve for be Velocity you would divide both sides by Velocity. The velocity will equal the momentum divided by the mass.
Work=Force*Distance so distance must be .82 meters
<u>Answer:</u>
"Where friction or rubbing results in the transfer of electrons between particles, objects can become negatively or positively charged."
<u>Explanation:</u>
The motion resistance of one moving object with respect to another is called as "Friction". It isn't a basic force, like gravity or electromagnetism. Alternatively, scientists believe it is the product of the electromagnetic attraction in two touching surfaces between charged particles.
The friction have formula:
Friction force (<em>f </em>) = coefficient of friction × normal force (N)
For an instances when one ride a bicycle, an example of rolling friction is the contact between the wheel and the way.