Answer:
Conservation of energy
Explanation:
The first law of thermodynamics is given by :
Here,
Q is amount of heat added to the system
is change in internal energy
W is amount of work done by the system
It is clear that the energy can be neither created nor destroyed, it remains conserved. Hence, first law of thermodynamics shows that conservation of energy.
Answer:
Work done, W = 5534.53 J
Explanation:
It is given that,
Force acting on the piano, F = 6157 N
It is pushed up a distance of 2.41 m friction less plank.
Let W is the work done in sliding the piano up the plank at a slow constant rate. It is given by :
Since, (in vertical direction)
W = 5534.53 J
So, the work done in sliding the piano up the plank is 5534.53 J. Hence, this is the required solution.
<u>Air pressure has no effect at all in an ideal gas approximation. This is because pressure and density both contribute to sound velocity equally, and in an ideal gas the two effects cancel out, leaving only the effect of temperature. Sound usually travels more slowly with greater altitude, due to reduced temperature.</u>