Answer:
Thickness of Styrofoam insulation is 0.02741 m.
Explanation:
Given that,
Height = 0.25 m
Depth = 0.5 m
Power = 400 W
Temperature = 33°C
We need to calculate the area of Styrofoam
Using formula of area

Put the value into the formula


Inner surface temperature of freezer

Outer surface temperature of freezer

We need to calculate the thickness of Styrofoam insulation
Using Fourier law,


Put the value into the formula


Hence, Thickness of Styrofoam insulation is 0.02741 m.
The 'Bulge', the 'Disk', the 'Spiral Arms', and the 'Halo' those are four parts of a spiral galaxy. Try finding out the many different types of galaxies to understand which is which.
Answer:
it tells you that the speed increases until about 20 seconds then keeps a steady pace for 20 seconds then the speed drops and stops at 55 seconds in the process.
<u>Given data</u>
Determine Internal energy of gas N₂, (U) = ?
Temperature (T) = 25° C
= 25+273 = 298 K,
Gas constant (R) = 8.31 J/ mol-K ,
Number of moles (n) = 3 moles,
<u>Internal energy of N₂ </u>
Internal energy is a property of thermodynamics, the concept of internal energy can be understand by ideal gas. For example N₂, the observations for oxygen and nitrogen at atmospheric temperatures, f=5, (where f is translational degrees of freedom).
So per kilogram of gas,
The internal energy (U) = 5/2 .n.R.T
= (5/2) × 3 × 8.31 ×298
= 18572.85 J
<em>The internal energy of the N₂ is 18,572.85 J and it is approximately equal to 18,600 J given in the option B.</em>
Answer:
The correct answer is d
Explanation:
In this exercise they ask us which statement is correct, for this we plan the solution of the problem, this is a Doppler effect problem, it is the frequency change due to the relative speed between the emitter and the receiver of sound.
The expression for the Doppler effect of a moving source is
f ’= (v / (v- + v_s) f
From this expression we see that if the speed the sound source is different from zero feels a change in the frequency.
The correct answer is d