Question

1`Solve the quadratic equation

5.00t² − 5.00t − 6.00 = 0

using the quadratic formula, finding both solutions.

t	=	(smaller value)
t	=	(larger value) 2`A monatomic ideal gas expands from 1.95 m3 to 2.55 m3 at a constant pressure of 2.50 ✕ 105 Pa. Find the following. (a) Find the work done on the gas. J (b) Find the thermal energy Q transferred into the gas by heat. J (c) Find the change in the internal energy of the gas. J

Answer 1

part A :

Work Done W = p dV

p is pressure

dV is change of Volume = (Vf - Vi)

so

W = 2.5*10^5 *(2.55 -1.95)

W = 1.5*10^5 Joules

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part B :

Heat Tranfered Q = n Cp dT

T1 = P1V1/nR

T1 = (2.5 *10^5 * 1.95)/(1 * 8.314)

T1 = 58636 K

T2 = (2.5 *10^5 *2.55)/(1 * 8.314)   

T2 = 76677.89 K

so

Q = 1 * 5/2 * 8.314 * (76677.89 - 58636)

Q = 3.75 *10^5 Joules

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part C:

Internal energy U = Q-W

U = (3.75 *10^5 - 1.5 *10^5)

U = 2.25*10^5 Joules