From Carnot's theorem, for any engine working between these two temperatures:
efficiency <= (1-tc/th) * 100
Given: tc = 300k (from question assuming it is not 5300 as it seems)
For a, th = 900k, efficiency = (1-300/900) = 70%
For b, th = 500k, efficiency = (1-300/500) = 40%
For c, th = 375k, efficiency = (1-300/375) = 20%
Hence in case of a and b, efficiency claimed is lesser than efficiency calculated, which is valid case and in case of c, however efficiency claimed is greater which is invalid.
Answer:
TEMPERATURE
Explanation:
When a wave is absorbed by a material medium, different phenomena occur, but the collisions with the other particles causes the energy to be transformed into internal energy in the atoms and molecules of the material, with TEMPERATURE measurements the increase in the internal energy of the material.
Answer: 1.91*10^8 N/m²
Explanation:
Given
Radius of the steel, R = 10 mm = 0.01 m
Length of the steel, L = 80 cm = 0.8 m
Force applied on the steel, F = 60 kN
Stress on the rod, = ?
Area of the rod, A = πr²
A = 3.142 * 0.01²
A = 0.0003142
Stress = Force applied on the steel/Area of the steel
Stress = F/A
Stress = 60*10^3 / 0.0003142
Stress = 1.91*10^8 N/m²
From the calculations above, we can therefore say, the stress on the rod is 1.91*10^8 N/m²
Answer:
2.13 x 10^-19 J or 0.53 eV
Explanation:
cut off wavelength, λo = 700 nm = 700 x 10^-9 m
λ = 400 nm = 400 x 10^-9 m
Use the energy equation

Where, K be the work function



K = 2.13 x 10^-19 J
K = 0.53 eV
As per angular momentum conservation we can say

here we know that

we know that




now from above equation



so speed is 4.4 m/s