# A heating element of resistance r is fitted inside an adiabatic cylinder which carries a frictionless piston of mass m and crosssection A as shown in diagram. The cylinder contains one mole of an ideal diatomic gas. The current flows through the element ?

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such that the temperature rises with time t as

#(C)# . the piston moves up with constant acceleration .

#(D)# . the piston moves up with constant velocity.

such that the temperature rises with time t as

##### 1 Answer

#### Explanation:

Well as the cylinder is adiabatic in nature,it will not release nor accept any heat other than the heat produced by the resistor.

Now.the pressure on the gas is solely due to the atmospheric pressure and weight of the piston,which don't change with the process.

So,it is an isobaric process.

Now,change in internal energy for an isobaric process is given as,

Now,

And,

So,

so,

So,option

Now,we know,power generated due to current flowing

Now,here,

Now,for an isobaric process

So,

or,

So,option

Now,work done in isobaric process is

now,

As,

so,

or,

or,

so,

So,

Compare with

So,the piston will move upward with constant acceleration.

So,option