Molecular Physics | Thermodynamics Answers

What is the final temperature of a glass-air mixture if the glass is initially  at 20.0°C and the air is initially at -30.0°C. Assume the mass of both  substances is 2.00 kg. 

An ideal gas with gamma=1.30 occupies 7.0 L at 300 K and 200 kPa pressure.

It is compressed adiabatically to 1/7 of its original volume, then cooled at constant volume to 300 K, and finally allowed to expand isothermally to 7.0 L.

How much work does the gas do during this process?

A. -980 J

B. 6400 J

C. -270 kJ

D. -6400 J

E. None of the above.

If 15.0 g of Ice at -25.0°C is mixed with a mass of antifreeze initially at  -3.00°C. If the final temperature of the mixture is -10.0°C, how much  antifreeze is present (Cantifreeze=2.24 x 102 J/KgoC)?

How much heat is lost by 2.50 kg of sand on a beach if the warmest part  of the day is 35.0°C and it cools to 3.00°C at night (c=840 J/kgoC)?

What substance can gain 40.0 kJ and only gain 25°C if 1.616 kg of the  substance is present?

The temperature of an ideal gas in a sealed 0.40m³ rigid container is reduced from 350 K to 270 K.The final pressure of the gas is 60 kPa. The molar heat capacity at constant volume of the gas is 28.0 J/(mol K). The heat absorbed by the gas is closest to

• A. -24 kJ.
•  B. -31 kJ.
•  C. 24 kJ.
•  D. 31 kJ.
•  E. None of the above.

The temperature of an ideal gas in a sealed 0.40m³ rigid container is reduced from 350 K to 270 K.The final pressure of the gas is 60 kPa. The molar heat capacity at constant volume of the gas is 28.0 J/(mol K). The heat absorbed by the gas is closest to

• A. -24 kJ.
•  B. -31 kJ.
•  C. 24 kJ.
•  D. 31 kJ.
•  E. None of the above.

Determine the resultant of the three forces acting on the gusset plate of a truss.

. Spherically symmetric charge distribution. Fig. 3-15 shows a spherical distribution of charge of radius R. The charge density  at any points depends only on the distance of the point from the center and not on the direction, a condition called spherical symmetry. Find an expression for E for points (a) outside and (b) inside the charge distribution. Note that the object in Fig. 3-15 cannot be a conductor. 

The charges and coordinates of two charged particles held fixed in the x-y plane are: q1 = +3.0x10^-6 C; x = 3.5, y = 0.5 cm, and q2 = - 4.0x10-6 C; x = - 2.0 cm, y = 1.5 cm. (a) Find the magnitude and direction of the force on q2. (b) where could you locate the third charge q3 = + 4.0x10^-6 C such the total force on q2 is zero?