Download App

11. thermodynamics — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysics11. thermodynamics1 Mark
MCQ
The $P-V$ diagram of a system undergoing thermodynamic transformation is shown in figure. The work done on the system in going from $A → B → C$ is $50 J$ and $ 20\, cal$ heat is given to the system. The change in internal energy between $A$ and $C$ is ...... $J$
  • A
    $34 $
  • B
    $70 $
  • C
    $84 $
  • ✓
    $134 $
✓

Answer

Correct option: D.
$134 $
d
(d) Heat given $\Delta Q   = 20\,cal = 20 \times 4.2\, = 84\,J$.

Work done $\Delta W = -50 J$         [As process is anticlockwise]

By first law of thermodynamics

==> $\Delta U = \Delta Q - \Delta W = 84 - ( - \,50)\, = 134J$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 11. thermodynamics→11. thermodynamics — all question types→Physics STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

In changing the state of thermodynamics from $A$ to $B$ state, the heat required is $Q$ and the work done by the system is $W.$ The change in its internal energy is
→
A metal wire has mass $(0.4 \pm 0.002)\,g$, radius $(0.3 \pm 0.001)\,mm$ and length $(5 \pm 0.02) \,cm$. The maximum possible percentage error in the measurement of density will nearly be $.......\%$
→
Three discs $A, B$ and $C$ having radii $2\; m, 4\;m,$ and $6 \;m$, respectively are coated with carbon black on their outer surfaces. The wavelengths corresponding to maximum intensity are $300\; nm, 400\; nm$ and $500\; nm$, respectively. The power radiated by them are $Q_A,Q_B$ and $Q_C$ respectively.
→
The Poisson's ratio cannot have the value
→
A wire $2 \,m$ in length suspended vertically stretches by $10 \,mm$ when mass of $10 \,kg$ is attached to the lower end. The elastic potential energy gain by the wire is ...... $J$ (take $g=10 \,m / s ^2$ )
→
A rocket of mass $M$ is launched vertically from the surface of the earth with an initial speed $V$. Assuming the radius of the earth to be $R$ and negligible air resistance, the maximum height attained by the rocket above the surface of the earth is
→
There is a rough black spot on a polished metallic plate. It is heated upto $1400 K$ approximately and then at once taken in a dark room. Which of the following statements is true
→
Two particles are projected simultaneously in the same vertical plane, from the same point on ground, but with same speeds but at different angles $( < 90^o )$ to the horizontal. The path followed by one, as seen by the other, is
→
A driver in a car, approaching a vertical wall notices that the frequency of his car horn, has changed from $440\, Hz$ to $480 \,Hz ,$ when it gets reflected from the wall. If the speed of sound in air is $345 \,m / s ,$ then the speed of the car is $.......km/hr$
→
The equation of state of some gases can be expressed as $\left( {P + \frac{a}{{{V^2}}}} \right)\,(V - b) = RT$. Here $P$ is the pressure, $V$ is the volume, $T$ is the absolute temperature and $a,\,b,\,R$ are constants. The dimensions of $'a'$ are
→