Answer:
a) 0 J
b) W = nRTln(Vf/Vi)
c) ΔQ = nRTln(Vf/Vi)
d) ΔQ = W
Explanation:
a) To find the change in the internal energy you use the 1st law of thermodynamics:
Q: heat transfer
W: work done by the gas
The gas is compressed isothermally, then, there is no change in the internal energy and you have
ΔU = 0 J
b) The work is done by the gas, not over the gas.
The work is given by the following formula:
n: moles
R: ideal gas constant
T: constant temperature
Vf: final volume
Vi: initial volume
Vf < Vi, then W < 0 and the work is done on the gas
c) The gas has been compressed. Thus, its temperature increases and heat has been transferred to the gas.
The amount of heat is equal to the work done W
d)
Assuming you are looking for the acceleration a:
1.
2.
where T is the tension and a is the acceleration of the blocks. The acceleration of the two blocks and the acceleration of the pulley must be equal.
The torque on the pulley is given by:
3.
where
and
.
Combining the three equations:
Answer:
C. Evaporating water from the container.
Explanation:
The concentration of solution changes when solvent or solute are added/removed from a solution.
Answer : The temperature when the water and pan reach thermal equilibrium short time later is, 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of aluminium = 
= specific heat of water = 
= mass of aluminum = 0.500 kg = 500 g
= mass of water = 0.250 kg = 250 g
= final temperature of mixture = ?
= initial temperature of aluminum = 
= initial temperature of water = 
Now put all the given values in the above formula, we get:
Therefore, the temperature when the water and pan reach thermal equilibrium short time later is,
PART A)
Conductivity of insulator is very small as there is no free electrons to conduct the current trough that medium
So here number of conduction electrons are very less in insulators
PART B)
Resistance is the property of a conducting medium which will oppose the flow of current trough it
Resistance of wire directly depends on its length so resistance of long wire will be more than the resistance of short wire
Resistance inversely depends on the area so if a wire has more crossectional area then its resistance must be small
PART C)
power of light bulb is defined as rate of electrical energy
it is given by formula
P = i V
here we know that
i = 1.46 A
V = 120 volts
so power is given as
