Answer:
W = - 118.24 J (negative sign shows that work is done on piston)
Explanation:
First, we find the change in internal energy of the diatomic gas by using the following formula:
![\Delta\ U = nC_{v}\Delta\ T](https://tex.z-dn.net/?f=%5CDelta%5C%20U%20%3D%20nC_%7Bv%7D%5CDelta%5C%20T)
where,
ΔU = Change in internal energy of gas = ?
n = no. of moles of gas = 0.0884 mole
Cv = Molar Specific Heat at constant volume = 5R/2 (for diatomic gases)
Cv = 5(8.314 J/mol.K)/2 = 20.785 J/mol.K
ΔT = Rise in Temperature = 18.8 K
Therefore,
![\Delta\ U = (0.0884\ moles)(20.785\ J/mol.K)(18.8\ K)\\\Delta\ U = 34.54\ J](https://tex.z-dn.net/?f=%5CDelta%5C%20U%20%3D%20%280.0884%5C%20moles%29%2820.785%5C%20J%2Fmol.K%29%2818.8%5C%20K%29%5C%5C%5CDelta%5C%20U%20%3D%2034.54%5C%20J)
Now, we can apply First Law of Thermodynamics as follows:
![\Delta\ Q = \Delta\ U + W](https://tex.z-dn.net/?f=%5CDelta%5C%20Q%20%3D%20%5CDelta%5C%20U%20%2B%20W)
where,
ΔQ = Heat flow = - 83.7 J (negative sign due to outflow)
W = Work done = ?
Therefore,
![-83.7\ J = 34.54\ J + W\\W = -83.7\ J - 34.54\ J\\](https://tex.z-dn.net/?f=-83.7%5C%20J%20%3D%2034.54%5C%20J%20%2B%20W%5C%5CW%20%3D%20-83.7%5C%20J%20-%2034.54%5C%20J%5C%5C)
<u>W = - 118.24 J (negative sign shows that work is done on piston)</u>
According to the inverse square law of light, <span>apparent brightness will decrease by a factor of 9. Use the formula </span>
![B=L/(4*pD^2)](https://tex.z-dn.net/?f=B%3DL%2F%284%2ApD%5E2%29)
, to check it.
Answer:
69000 V
Explanation:
E = Electric field = ![3\times 10^6\ V/m](https://tex.z-dn.net/?f=3%5Ctimes%2010%5E6%5C%20V%2Fm)
d = Distance between plates = 2.3 cm
When we multiply the electric field strength and the distance between the plates of a capacitor we get the maximum voltage.
Maximum voltage is given by
![V_m=Ed\\\Rightarrow V_m=3\times 10^6\times 2.3\times 10^{-2}\\\Rightarrow V_m=69000\ V](https://tex.z-dn.net/?f=V_m%3DEd%5C%5C%5CRightarrow%20V_m%3D3%5Ctimes%2010%5E6%5Ctimes%202.3%5Ctimes%2010%5E%7B-2%7D%5C%5C%5CRightarrow%20V_m%3D69000%5C%20V)
The highest voltage the students can use is 69000 V
<span>i think the average speed was 54.54 (mph)</span>