12583 + Mcqs in Physics Page 229 McqOptions

11401.	An ideal refrigerator has a freezer at a temperature of \[-13{}^\circ C.\] The coefficient of performance of the engine is 5. The temperature of the air (to which heat is rejected) will be
A.	325°C
B.	325K
C.	39°C
D.	320°C
Answer» D. 320°C

Discussion

11402.	A Carnot engine operates between \[{{227}^{o}}C\] and \[{{27}^{o}}C.\] Efficiency of the engine will be
A.	\[\frac{1}{3}\]
B.	\[\frac{2}{5}\]
C.	\[\frac{3}{4}\]
D.	\[\frac{3}{5}\]
Answer» C. \[\frac{3}{4}\]

Discussion

11403.	An ideal gas heat engine operates in a Carnot's cycle between \[{{227}^{o}}C\] and \[{{127}^{o}}C\]. It absorbs 6 × 104 J at high temperature. The amount of heat converted into work is ....
A.	\[4.8\times {{10}^{4}}\,J\]
B.	\[3.5\times {{10}^{4}}\,J\]
C.	\[1.6\times {{10}^{4}}\,J\]
D.	\[1.2\times {{10}^{4}}\,J\]
Answer» E.

Discussion

11404.	Which relation is correct for isometric process
A.	\[\Delta Q=\Delta U\]
B.	\[\Delta W=\Delta U\]
C.	\[\Delta Q=\Delta W\]
D.	None of these
Answer» B. \[\Delta W=\Delta U\]

Discussion

11405.	A Container having 1 mole of a gas at a temperature 27°C has a movable piston which maintains at constant pressure in container of 1 atm. The gas is compressed until temperature becomes 127°C. The work done is (Cp for gas is 7.03 cal/molK)
A.	703 J
B.	814 J
C.	121 J
D.	2035 J
Answer» C. 121 J

Discussion

11406.	When heat in given to a gas in an isobaric process, then
A.	The work is done by the gas
B.	Internal energy of the gas increases
C.	Both [a] and [b]
D.	None from [a] and [b]
Answer» D. None from [a] and [b]

Discussion

11407.	The internal energy of the gas increases In
A.	Adiabatic expansion
B.	Adiabatic compression
C.	Isothermal expansion
D.	Isothermal compression
Answer» C. Isothermal expansion

Discussion

11408.	A diatomic gas initially at 18°C is compressed adiabatically to one-eighth of its original volume. The temperature after compression will be
A.	\[{{10}^{o}}C\]
B.	\[{{887}^{o}}C\]
C.	\[668K\]
D.	\[{{144}^{o}}C\]
Answer» D. \[{{144}^{o}}C\]

Discussion

11409.	The adiabatic elasticity of hydrogen gas \[(\gamma =1.4)\] at NTP is
A.	\[1\times {{10}^{5}}\ N/{{m}^{2}}\]
B.	\[1\times {{10}^{-8}}\ N/m2\]
C.	\[1.4\ N/{{m}^{2}}\]
D.	\[1.4\times {{10}^{5}}N/{{m}^{2}}\]
Answer» E.

Discussion

11410.	A gas at NTP is suddenly compressed to one-fourth of its original volume. If \[\gamma \] is supposed to be \[\frac{3}{2}\], then the final pressure is
A.	4 atmosphere
B.	\[\frac{3}{2}\] atmosphere
C.	8 atmosphere
D.	\[\frac{1}{4}\] atmosphere
Answer» D. \[\frac{1}{4}\] atmosphere

Discussion

11411.	One mole of an ideal gas expands at a constant temperature of 300 K from an initial volume of 10 litres to a final volume of 20 litres. The work done in expanding the gas is (R = 8.31 J/mole-K)
A.	750 joules
B.	1728 joules
C.	1500 joules
D.	3456 joules
Answer» C. 1500 joules

Discussion

11412.	If a system undergoes contraction of volume then the work done by the system will be
A.	Zero
B.	Negligible
C.	Negative
D.	Positive
Answer» D. Positive

Discussion

11413.	Which of the following parameters does not characterize the thermodynamic state of matter
A.	Volume
B.	Temperature
C.	Pressure
D.	Work
Answer» E.

Discussion

11414.	An ideal gas heat engine operates in Carnot cycle between 227°C and 127°C. It absorbs \[6\times {{10}^{4}}\] cals of heat at higher temperature. Amount of heat converted to work is
A.	\[2.4\times {{10}^{4}}\]cal
B.	\[6\times {{10}^{4}}\] cal
C.	\[1.2\times {{10}^{4}}\] cal
D.	\[4.8\times {{10}^{4}}\] cal
Answer» D. \[4.8\times {{10}^{4}}\] cal

Discussion

11415.	A carnot engine has the same efficiency between 800 K to 500 K and x K to 600 K. The value of x is
A.	1000 K
B.	960 K
C.	846 K
D.	754 K
Answer» C. 846 K

Discussion

11416.	For a reversible process, necessary condition is
A.	In the whole cycle of the system, the loss of any type of heat energy should be zero
B.	That the process should be too fast
C.	That the process should be slow so that the working substance should remain in thermal and mechanical equilibrium with the surroundings
D.	The loss of energy should be zero and it should be quasistatic
Answer» E.

Discussion

11417.	Unit mass of a liquid with volume \[{{V}_{1}}\] is completely changed into a gas of volume \[{{V}_{2}}\] at a constant external pressure P and temperature T. If the latent heat of evaporation for the given mass is L, then the increase in the internal energy of the system is
A.	Zero
B.	\[P({{V}_{2}}-{{V}_{1}})\]
C.	\[L-P({{V}_{2}}-{{V}_{1}})\]
D.	L
Answer» D. L

Discussion

11418.	A gas for which \[\gamma =1.5\]is suddenly compressed to\[\frac{1}{4}\]th of the initial volume. Then the ratio of the final to the initial pressure is
A.	0.0527777777777778
B.	0.0472222222222222
C.	0.0444444444444444
D.	0.334027777777778
Answer» E.

Discussion

11419.	In an adiabatic process, the state of a gas is changed from \[{{P}_{1}},{{V}_{1}},{{T}_{1}},\] to \[{{P}_{2}},{{V}_{2}},{{T}_{2}}\]. Which of the following relation is correct
A.	\[{{T}_{1}}{{V}_{1}}^{\gamma -1}={{T}_{2}}{{V}_{2}}^{\gamma -1}\]
B.	\[{{P}_{1}}{{V}_{1}}^{\gamma -1}={{P}_{2}}{{V}_{2}}^{\gamma -1}\]
C.	\[{{T}_{1}}{{P}_{1}}^{\gamma }={{T}_{2}}{{P}_{2}}^{\gamma }\]
D.	\[{{T}_{1}}{{V}_{1}}^{\gamma }={{T}_{2}}{{V}_{2}}^{\gamma }\]
Answer» B. \[{{P}_{1}}{{V}_{1}}^{\gamma -1}={{P}_{2}}{{V}_{2}}^{\gamma -1}\]

Discussion

11420.	Helium at \[{{27}^{o}}C\] has a volume of 8 litres. It is suddenly compressed to a volume of 1 litre. The temperature of the gas will be \[[\gamma =5/3]\]
A.	\[{{108}^{o}}C\]
B.	\[{{9327}^{o}}C\]
C.	\[{{1200}^{o}}C\]
D.	\[{{927}^{o}}C\]
Answer» E.

Discussion

11421.	One gm mol of a diatomic gas \[(\gamma =1.4)\] is compressed adiabatically so that its temperature rises from \[{{27}^{o}}C\] to \[{{127}^{o}}C\]. The work done will be
A.	2077.5 joules
B.	207.5 joules
C.	207.5 ergs
D.	None of the above
Answer» B. 207.5 joules

Discussion

11422.	An ideal gas at \[{{27}^{o}}C\] is compressed adiabatically to \[\frac{8}{27}\] of its original volume. If \[\gamma =\frac{5}{3}\], then the rise in temperature is
A.	450 K
B.	375 K
C.	225 K
D.	405 K
Answer» C. 225 K

Discussion

11423.	The pressure in the tyre of a car is four times the atmospheric pressure at 300 K. If this tyre suddenly bursts, its new temperature will be \[(\gamma =1.4)\]
A.	\[300\,{{(4)}^{1.4/0.4}}\]
B.	\[300\,{{\left( \frac{1}{4} \right)}^{-0.4/1.4}}\]
C.	\[300\,{{(2)}^{-0.4/1.4}}\]
D.	\[300\,{{(4)}^{-0.4/1.4}}\]
Answer» E.

Discussion

11424.	540 calories of heat convert 1 cubic centimeter of water at \[{{100}^{o}}C\] into 1671 cubic centimeter of steam at \[{{100}^{o}}C\] at a pressure of one atmosphere. Then the work done against the atmospheric pressure is nearly
A.	540 cal
B.	40 cal
C.	Zero cal
D.	500 cal
Answer» C. Zero cal

Discussion

11425.	A monoatomic ideal gas goes through a process \[p={{p}_{0}}-\alpha V\] where \[{{p}_{0}}\] and \[\alpha \] are positive constants and V is its volume. At what volume will the entropy of gas be maximum?
A.	\[\frac{5{{p}_{0}}}{6\alpha }\]
B.	\[\frac{{{p}_{0}}}{2\alpha }\]
C.	\[\frac{{{p}_{0}}}{4\alpha }\]
D.	\[\frac{5{{p}_{0}}}{8\alpha }\]
Answer» E.

Discussion

11426.	A Carnot engine is working between \[127{}^\circ C\] and \[27{}^\circ C.~\]The increase in efficiency will be maximum when the temperature of
A.	the source is increased by \[50{}^\circ C\]
B.	the sink is decreased by\[50{}^\circ C\]
C.	source is increased by \[25{}^\circ C\]and that of sink is decreased by \[25{}^\circ C\]
D.	both source and sink are decreased by \[25{}^\circ C\]
Answer» C. source is increased by \[25{}^\circ C\]and that of sink is decreased by \[25{}^\circ C\]

Discussion

11427.	A Carnot engine whose efficiency is 50% has an exhaust temperature of 500 K. If the efficiency is to be 60% with the same intake temperature, the exhaust temperature must be (in K)
A.	800
B.	200
C.	400
D.	600
Answer» D. 600

Discussion

11428.	A diatomic ideal gas undergoes a thermodynamic change according to the P-V diagram shown in the figure. The total heat given to the gas is nearly (use ln \[2=0.7\])
A.	\[2.5{{P}_{0}}{{V}_{0}}\]
B.	\[1.4{{P}_{0}}{{V}_{0}}\]
C.	\[1.1{{P}_{0}}{{V}_{0}}\]
D.	\[3.9{{P}_{0}}{{V}_{0}}\]
Answer» E.

Discussion

11429.	A steam engine takes 0.1 kg of steam at \[100{}^\circ C\] per minute and cools it down to \[20{}^\circ C.\]What is the heat rejected by the steam engine per second? [Latent heat of vaporization of steam = 540 cal
A.	\[6.2\times {{10}^{4}}cal/\sec \]
B.	\[1.03\times {{10}^{3}}cal/\sec \]
C.	\[62\times {{10}^{3}}cal/sec\]
D.	None of these
Answer» C. \[62\times {{10}^{3}}cal/sec\]

Discussion

11430.	A 500 ml sealed cylinder contains nitrogen at a pressure of 1 atm. A tiny glass tube lies at the bottom of the cylinder. Its volume is 0.50 ml and it contains hydrogen at a pressure of 4.5 atm. The glass tube is broken so that hydrogen also fills the cylinder. The new pressure in the cylinder is \[(1\text{ }atm=1\times 105N/{{m}^{2}})\]
A.	76.34 cm Hg
B.	82.40 cm Hg
C.	94.24 cm Hg
D.	104.34 cm Hg
Answer» B. 82.40 cm Hg

Discussion

11431.	The state of an ideal gas is changed through an isothermal process at temperature \[{{T}_{0}}\] as shown in figure. The work done by gas in going from state B to C is double the work done by gas in going from state A to B. If the pressure in the state B is \[{{P}_{0}}/2\] then the pressure of the gas in state C is
A.	\[{{P}_{0}}/2\]
B.	\[{{P}_{0}}/4\]
C.	\[{{P}_{0}}/6\]
D.	\[{{P}_{0}}/8\]
Answer» E.

Discussion

11432.	One mole of an ideal gas at an initial temperature of T K does 6R joules of word adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is 5/3, the final temperature of gas will be
A.	\[(T-4)K\]
B.	\[(T+2.4)K\]
C.	\[(T-2.4)K\]
D.	\[(T+4)K\]
Answer» B. \[(T+2.4)K\]

Discussion

11433.	A monatomic ideal gas, initially at temperature \[{{T}_{1}}\] is enclosed in a cylinder fitted with a frictionless piston. The gas is allowed to expand adiabatically to a temperature \[{{T}_{2}}\,\] by releasing the piston suddenly. If \[{{L}_{1}}\] and \[{{L}_{2}}\] are the length of the gas column before and after expansion respectively, then \[\frac{{{T}_{1}}}{{{T}_{2}}}\] is given by
A.	\[{{\left( \frac{{{L}_{1}}}{{{L}_{2}}} \right)}^{2/3}}\]
B.	\[\frac{{{L}_{1}}}{{{L}_{2}}}\]
C.	\[\frac{{{L}_{2}}}{{{L}_{1}}}\]
D.	\[{{\left( \frac{{{L}_{2}}}{{{L}_{1}}} \right)}^{2/3}}\]
Answer» E.

Discussion

11434.	For an ideal gas graph is shown for three processes, Process 1, 2 and 3 are respectively.
A.	Isobaric, adiabatic isochoric
B.	Adiabatic, isobaric, isochoric
C.	Isochoric, adiabatic, isobaric
D.	Isochoric, isobaric, adiabatic
Answer» E.

Discussion

11435.	In the P-V diagram, I is the initial state and F is the final state. The gas goes from I to F by (i) IAF, (ii) IBF, (iii) ICE The heat absorbed by the gas is
A.	the same in all three processes
B.	the same in (i) and (ii)
C.	greater in (i) than in (ii)
D.	the-same in (i) and (iii)
Answer» D. the-same in (i) and (iii)

Discussion

11436.	When a system is taken a from state i to state f along the path iaf, it is found that \[Q=50\]cal and \[W=20cal.\], Along the path ibf \[Q=36\]cal. W along the path ibf is
A.	14 cal
B.	6 cal
C.	16 cal
D.	66 cal
Answer» C. 16 cal

Discussion

11437.	The internal energy change in a system that has absorbed 2 Kcal of heat and done 500 J of work is
A.	8900 J
B.	6400 J
C.	5400 J
D.	7900 J
Answer» E.

Discussion

11438.	The specific heat of a gas in an isothermal process is
A.	infinite
B.	zero
C.	negative
D.	remains constant
Answer» B. zero

Discussion

11439.	A cube of side 5 cm made of iron and having a mass of 1500 g is heated from \[25{}^\circ C\] to \[400{}^\circ C.\]The specific heat for iron is \[0.12\text{ }cal/g{}^\circ C\]and the coefficient of volume expansion is \[3.5\times {{10}^{-5}}/{}^\circ C,\]the change in the internal energy of the cube is (atm pressure \[1\times {{10}^{5}}N/{{m}^{2}}\])
A.	320 kJ
B.	282 kJ
C.	141 kJ
D.	423 kJ
Answer» C. 141 kJ

Discussion

11440.	The first law of thermodynamics is concerned with the conservation of [MP PMT 1987; CBSE PMT 1990, 92; AFMC 1997; CPMT 1999; BHU 1999; DCE 2000; BCECE 2003]
A.	Momentum
B.	Energy
C.	Mass
D.	Temperature
Answer» C. Mass

Discussion

11441.	Assertion : Work and heat are two equivalent form of energy. Reason : Work is the transfer of mechanical energy irrespective of temperature difference, whereas heat is the transfer of thermal energy because of temperature difference only.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

11442.	A system goes from A to B via two processes I and II as shown in figure. If \[\Delta {{U}_{1}}\] and \[\Delta {{U}_{2}}\] are the changes in internal energies in the processes I and II respectively, then [AIEEE 2005]
A.	\[\Delta {{U}_{\text{II}}}>\Delta {{U}_{\text{I}}}\]
B.	\[\Delta {{U}_{\text{II}}}<\Delta {{U}_{\text{I}}}\]
C.	\[\Delta {{U}_{\text{I}}}=\Delta {{U}_{\text{II}}}\]
D.	Relation between \[\Delta {{U}_{\text{I}}}\] and \[\Delta {{U}_{\text{II}}}\] can not be determined
Answer» D. Relation between \[\Delta {{U}_{\text{I}}}\] and \[\Delta {{U}_{\text{II}}}\] can not be determined

Discussion

11443.	If R = universal gas constant, the amount of heat needed to raise the temperature of 2 mole of an ideal monoatomic gas from 273K to 373K when no work is done [MP PET 1990]
A.	100 R
B.	150 R
C.	300 R
D.	500 R
Answer» D. 500 R

Discussion

11444.	In a mechanical refrigerator, the low temperature coils are at a temperature of ? 23°C and the compressed gas in the condenser has a temperature of 27°C. The theoretical coefficient of performance is [UPSEAT 2001]
A.	5
B.	8
C.	6
D.	6.5
Answer» B. 8

Discussion

11445.	The P-V graph of an ideal gas cycle is shown here as below. The adiabatic process is described by [CPMT 1985; UPSEAT 2003]
A.	AB and BC
B.	AB and CD
C.	BC and DA
D.	BC and CD
Answer» D. BC and CD

Discussion

11446.	A particle has simple harmonic motion. The equation of its motion is \[x=5\sin \left( 4t-\frac{\pi }{6} \right)\], where x is its displacement. If the displacement of the particle is 3 units, then it velocity is [MP PMT 1994]
A.	\[\frac{2\pi }{3}\]
B.	\[\frac{5\pi }{6}\]
C.	\[20\]
D.	\[16\]
Answer» E.

Discussion

11447.	The velocity of a particle performing simple harmonic motion, when it passes through its mean position is [MH CET (Med.) 2002; BCECE 2004]
A.	Infinity
B.	Zero
C.	Minimum
D.	Maximum
Answer» E.

Discussion

11448.	The acceleration of a particle performing S.H.M. is \[12cm/se{{c}^{2}}\] at a distance of 3 cm from the mean position. Its time period is [MP PET 1996; MP PMT 1997]
A.	0.5 sec
B.	1.0 sec
C.	2.0 sec
D.	3.14 sec
Answer» E.

Discussion

11449.	The kinetic energy of a particle executing S.H.M. is 16 J when it is in its mean position. If the amplitude of oscillations is 25 cm and the mass of the particle is 5.12 kg, the time period of its oscillation is [Haryana CEE 1996; AFMC 1998]
A.	\[\frac{\pi }{5}\]sec
B.	\[2\pi \]sec
C.	\[20\pi \]sec
D.	\[5\pi \]sec
Answer» B. \[2\pi \]sec

Discussion

11450.	The motion of a particle executing S.H.M. is given by \[x=0.01\sin 100\pi (t+.05)\], where x is in metres and time is in seconds. The time period is [CPMT 1990]
A.	0.01 sec
B.	0.02 sec
C.	0.1 sec
D.	0.2 sec
Answer» C. 0.1 sec

Discussion

Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

An ideal refrigerator has a freezer at a temperature of \[-13{}^\circ C.\] The coefficient of performance of the engine is 5. The temperature of the air (to which heat is rejected) will be

A Carnot engine operates between \[{{227}^{o}}C\] and \[{{27}^{o}}C.\] Efficiency of the engine will be

An ideal gas heat engine operates in a Carnot's cycle between \[{{227}^{o}}C\] and \[{{127}^{o}}C\]. It absorbs 6 × 104 J at high temperature. The amount of heat converted into work is ....

Which relation is correct for isometric process

A Container having 1 mole of a gas at a temperature 27°C has a movable piston which maintains at constant pressure in container of 1 atm. The gas is compressed until temperature becomes 127°C. The work done is (Cp for gas is 7.03 cal/molK)

When heat in given to a gas in an isobaric process, then

The internal energy of the gas increases In

A diatomic gas initially at 18°C is compressed adiabatically to one-eighth of its original volume. The temperature after compression will be

The adiabatic elasticity of hydrogen gas \[(\gamma =1.4)\] at NTP is

A gas at NTP is suddenly compressed to one-fourth of its original volume. If \[\gamma \] is supposed to be \[\frac{3}{2}\], then the final pressure is

One mole of an ideal gas expands at a constant temperature of 300 K from an initial volume of 10 litres to a final volume of 20 litres. The work done in expanding the gas is (R = 8.31 J/mole-K)

If a system undergoes contraction of volume then the work done by the system will be

Which of the following parameters does not characterize the thermodynamic state of matter

An ideal gas heat engine operates in Carnot cycle between 227°C and 127°C. It absorbs \[6\times {{10}^{4}}\] cals of heat at higher temperature. Amount of heat converted to work is

A carnot engine has the same efficiency between 800 K to 500 K and x K to 600 K. The value of x is

For a reversible process, necessary condition is

Unit mass of a liquid with volume \[{{V}_{1}}\] is completely changed into a gas of volume \[{{V}_{2}}\] at a constant external pressure P and temperature T. If the latent heat of evaporation for the given mass is L, then the increase in the internal energy of the system is

A gas for which \[\gamma =1.5\]is suddenly compressed to\[\frac{1}{4}\]th of the initial volume. Then the ratio of the final to the initial pressure is

In an adiabatic process, the state of a gas is changed from \[{{P}_{1}},{{V}_{1}},{{T}_{1}},\] to \[{{P}_{2}},{{V}_{2}},{{T}_{2}}\]. Which of the following relation is correct

Helium at \[{{27}^{o}}C\] has a volume of 8 litres. It is suddenly compressed to a volume of 1 litre. The temperature of the gas will be \[[\gamma =5/3]\]

One gm mol of a diatomic gas \[(\gamma =1.4)\] is compressed adiabatically so that its temperature rises from \[{{27}^{o}}C\] to \[{{127}^{o}}C\]. The work done will be

An ideal gas at \[{{27}^{o}}C\] is compressed adiabatically to \[\frac{8}{27}\] of its original volume. If \[\gamma =\frac{5}{3}\], then the rise in temperature is

The pressure in the tyre of a car is four times the atmospheric pressure at 300 K. If this tyre suddenly bursts, its new temperature will be \[(\gamma =1.4)\]

540 calories of heat convert 1 cubic centimeter of water at \[{{100}^{o}}C\] into 1671 cubic centimeter of steam at \[{{100}^{o}}C\] at a pressure of one atmosphere. Then the work done against the atmospheric pressure is nearly

A monoatomic ideal gas goes through a process \[p={{p}_{0}}-\alpha V\] where \[{{p}_{0}}\] and \[\alpha \] are positive constants and V is its volume. At what volume will the entropy of gas be maximum?

A Carnot engine is working between \[127{}^\circ C\] and \[27{}^\circ C.~\]The increase in efficiency will be maximum when the temperature of

A Carnot engine whose efficiency is 50% has an exhaust temperature of 500 K. If the efficiency is to be 60% with the same intake temperature, the exhaust temperature must be (in K)

A diatomic ideal gas undergoes a thermodynamic change according to the P-V diagram shown in the figure. The total heat given to the gas is nearly (use ln \[2=0.7\])

A steam engine takes 0.1 kg of steam at \[100{}^\circ C\] per minute and cools it down to \[20{}^\circ C.\]What is the heat rejected by the steam engine per second? [Latent heat of vaporization of steam = 540 cal

One mole of an ideal gas at an initial temperature of T K does 6R joules of word adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is 5/3, the final temperature of gas will be

For an ideal gas graph is shown for three processes, Process 1, 2 and 3 are respectively.

In the P-V diagram, I is the initial state and F is the final state. The gas goes from I to F by (i) IAF, (ii) IBF, (iii) ICE The heat absorbed by the gas is

When a system is taken a from state i to state f along the path iaf, it is found that \[Q=50\]cal and \[W=20cal.\], Along the path ibf \[Q=36\]cal. W along the path ibf is

The internal energy change in a system that has absorbed 2 Kcal of heat and done 500 J of work is

The specific heat of a gas in an isothermal process is

The first law of thermodynamics is concerned with the conservation of [MP PMT 1987; CBSE PMT 1990, 92; AFMC 1997; CPMT 1999; BHU 1999; DCE 2000; BCECE 2003]

Assertion : Work and heat are two equivalent form of energy. Reason : Work is the transfer of mechanical energy irrespective of temperature difference, whereas heat is the transfer of thermal energy because of temperature difference only.

A system goes from A to B via two processes I and II as shown in figure. If \[\Delta {{U}_{1}}\] and \[\Delta {{U}_{2}}\] are the changes in internal energies in the processes I and II respectively, then [AIEEE 2005]

If R = universal gas constant, the amount of heat needed to raise the temperature of 2 mole of an ideal monoatomic gas from 273K to 373K when no work is done [MP PET 1990]

In a mechanical refrigerator, the low temperature coils are at a temperature of ? 23°C and the compressed gas in the condenser has a temperature of 27°C. The theoretical coefficient of performance is [UPSEAT 2001]

The P-V graph of an ideal gas cycle is shown here as below. The adiabatic process is described by [CPMT 1985; UPSEAT 2003]

A particle has simple harmonic motion. The equation of its motion is \[x=5\sin \left( 4t-\frac{\pi }{6} \right)\], where x is its displacement. If the displacement of the particle is 3 units, then it velocity is [MP PMT 1994]

The velocity of a particle performing simple harmonic motion, when it passes through its mean position is [MH CET (Med.) 2002; BCECE 2004]

The acceleration of a particle performing S.H.M. is \[12cm/se{{c}^{2}}\] at a distance of 3 cm from the mean position. Its time period is [MP PET 1996; MP PMT 1997]

The kinetic energy of a particle executing S.H.M. is 16 J when it is in its mean position. If the amplitude of oscillations is 25 cm and the mass of the particle is 5.12 kg, the time period of its oscillation is [Haryana CEE 1996; AFMC 1998]

The motion of a particle executing S.H.M. is given by \[x=0.01\sin 100\pi (t+.05)\], where x is in metres and time is in seconds. The time period is [CPMT 1990]