Assertion: Water kept in an open vessel will quickly evaporate on the surface of the moon.
Reason: The temperature at the surface of the moon is much higher than boiling point of water.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion: For an isothermal process in an ideal gas, the heat obsorbed by the gas is entirely used in the work done by the gas.
Reason: During a process taking place in a system, the temperature remains constant then the process is isothermal.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
B.
If both assertion and reason are true but reason is not the correct explanation of assertion
In case of an ideal gas internal energy depends only upon the temperature of the gas. Therefore, if an ideal gas undergoes an isothermal process, there will be no change in its internal energy
( ΔU = 0)
⇒ Q = W
A slab consists of two layers of different materials of the same thickness and having thermal conductivities K1 and K2 are connected in series. The equivalent thermal conductivity of the slab is
K1 + K2
A certain gas is taken to the five states represented by dots in the graph. The plotted lines are isotherms. Order of the most portable speed νp of the molecules at these five states is
νp at 3 > νp at 1 = νp at 2 > νp at 4 = νp at 5
νp at 1 > νp at 2 = νp at 3 > νp at 4 > νp at 5
νp at 3 > νp at 2 = νp at 4 > νp at 1 = νp at 5
insufficient information to predict the result
Two heater wires, made of the same material and having the same length and the same radius, are first connected in series and then in parallel to a constant potential difference. If the rates of I heat produced in the two cases are Hs and HP respectively, then Hs/HP will be
1/2
2
1/4
4
In an adiabatic change , the pressure and temperature of a monoatomic gas are relted as P ∝ TC, where C equals
Assertion: Ferro magnetic substances become paramagnetic above Curie temperature.
Reason: Domains are destroyed at high temperature.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion: In free expansion of an ideal gas, the entropy increases.
Reason: Entropy increases in all natural processes.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
By sucking through a straw, a student can reduce the pressure in his lungs to 750 mm of Hg ( densiy = 13.6 g/cm3). Using the straw, he can drink water from a glass upto a maximum depth of
10 cm
75 cm
13.6 cm
1.36 cm
When you make ice cubes, the entropy of water
does not change
increase
decreases
may either increase or decrease depending on the process used