Question

1200 J of heat are added to a sample of gas while the gas does 400 J of work on the environment. What is the change in internal energy of the gas​

Answer 1

iska shayad 300 joule hai

Answer 2

Given:

1200 J of heat are added to a sample of gas while the gas does 400 J of work on the environment.

To find:

Change in internal energy of the gas ?

Calculation:

In this type of questions , it is best to apply the 1st Equation of Thermodynamics:

$\boxed{\rm\therefore \: \Delta Q = \Delta U + W}$

• Here ∆Q is heat change of the system, ∆U is change in internal energy, W is work done.

• Since , heat was added to the system, sign of "∆Q" will be positive.

• Since, work was done by system on surrounding, sign of "W" will also be positive.

$\rm = > \: 1200 = \Delta U + 400$

$\rm = > \:\Delta U = 1200 - 400$

$\rm = > \:\Delta U = 800 \: joule$

So, change in internal energy (∆U) is +800 Joule.

Hope It Helps.