Answer:
Explanation:
The work done
and the energy taken
by a heat engine are related to the efficiency
by the expression

The efficiency is
=25%, the numerical form of this percentage is 0.25 and the energy taken is
=200J. Replacing in the formula:

Answer:
1/2mv² = ke²
Explanation:
Let's suppose the material in question is a spring with spring constant k, mass m and position k, the kinetic energy possessed by the string will be;
K.E = 1/2mass×velocity² i.e 1/2mv²
Its elastic potential energy will be the work done on the spring when stretched which is equal to 1/2kx²
E.P = 1/2kx²
The equation describing the case where the kinetic energy is twice the elastic potential energy will be;
K.E = 2EP... 1)
Substituting the KE and EP formula into (1), we have;
1/2mv² = 2(1/2ke²)
1/2mv² = ke² which gives the required equation
Explanation:
1. Mass of the proton, 
Wavelength, 
We need to find the potential difference. The relationship between potential difference and wavelength is given by :



V = 45.83 volts
2. Mass of the electron, 
Wavelength, 
We need to find the potential difference. The relationship between potential difference and wavelength is given by :




V = 84109.27 volt
Hence, this is the required solution.
Answer:
ΔU = - 310.6 J (negative sign indicates decrease in internal energy)
W = 810.6 J
Explanation:
a.
Using first law of thermodynamics:
Q = ΔU + W
where,
Q = Heat Absorbed = 500 J
ΔU = Change in Internal Energy of Gas = ?
W = Work Done = PΔV =
P = Pressure = 2 atm = 202650 Pa
ΔV = Change in Volume = 10 L - 6 L = 4 L = 0.004 m³
Therefore,
Q = ΔU + PΔV
500 J = ΔU + (202650 Pa)(0.004 m³)
ΔU = 500 J - 810.6 J
<u>ΔU = - 310.6 J (negative sign indicates decrease in internal energy)</u>
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b.
The work done can be simply calculated as:
W = PΔV
W = (202650 Pa)(0.004 m³)
<u>W = 810.6 J</u>