A) initial volume
We can calculate the initial volume of the gas by using the ideal gas law:

where

is the initial pressure of the gas

is the initial volume of the gas

is the number of moles

is the gas constant

is the initial temperature of the gas
By re-arranging this equation, we can find

:

2) Now the gas cools down to a temperature of

while the pressure is kept constant:

, so we can use again the ideal gas law to find the new volume of the gas

3) In a process at constant pressure, the work done by the gas is equal to the product between the pressure and the difference of volume:

by using the data we found at point 1) and 2), we find

where the negative sign means the work is done by the surrounding on the gas.
Answer:
The magnitude of the electric field is 5.75 N/C towards positive x- axis.
Explanation:
Given that,
Point charge at origin = 2 nC
Second charge = 5 nC
Distance at x axis = 8 m
We need to calculate the electric field at the point x = 2 m
Using formula of electric field

Put the value into the formula


The direction is toward positive x- axis.
Hence, The magnitude of the electric field is 5.75 N/C towards positive x- axis.
Answer:
F = 200 N
Explanation:
Given that,
The mass suspended from the rope, m = 20 kg
We need to find the resultant force acting on the rope. The resultant force on the rope is equal to its weight such that,
F = mg
Where
g is acceleration due to gravity
Put all the values,
F = 20 kg × 10 m/s²
F = 200 N
So, the resultant force on the mass is 200 N.
Because melting point<span> and </span>freezing point<span> describe the</span>same<span> transition of matter, in this case from liquid to solid (</span>freezing) or equivalently, from solid to liquid (melting<span>).</span>