70 calories of heat are required to raise the temperature of 2 moles of an ideal gas at constant pressure from 30°C to 35°C. The amount of heat required to raise the temperature of the same sample of the gas increases with through the same range at constant volume is (Gas constant= 1·99 cal/K-mole)
30 cal
50 cal
70 cal
90 cal
3 mole of hydrogen is mixed with 1 mole of neon. The molar specific heat at constant pressure is
A bottle weighing 220 g and of area of cross-section 50 cm2, and height 4 cm oscillates on the surface of water in vertical position. Its frequency of oscillation is
1.5 Hz
2.5 Hz
3.5 Hz
4.5 Hz
The time period of a particle undergoing SHM is 16 s. It starts motion from the mean position. After 2 s, its velocity is 0.4 m s-1 .The amplitude is
1.44 m
0.72 m
2.88 m
0.36 m
A 5.5 metre length of string has a mass of 0.035 kg. If the tension in the string is 77 N, the velocity of the wave on the string is
210 m s-1
40 m s-1
110 m s-1
55 m s-1
Assertion: Current is passed through a metallic wire so that it becomes red hot. When cold water is poured on half of its portion, the rest of the half portion becomes more hot.
Reason: Resistance decreases due to decrease in 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: When height of a tube is less than liquid rise in the capillary tube, the liquid does not overflow.
Reason: Product of radius of meniscus and height of liquid in the capillary tube always remain constant.
If both assertion and reason are true and reason is the correct explanation of assertion.
f 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.
A.
If both assertion and reason are true and reason is the correct explanation of assertion.
When capillary is dipped in water, it starts rising up due o pilling form the solid-vapor interface.
As
h = = a finite constant
Hence when the tube is of insufficient length, radius of curvature of the liquid meniscus increases, so as to maintain the product hR a finite constant, i.e. as h decreases, R increases and the liquid meniscus becomes more and more flat, but the liquid does not overflow.
Assertion: The periodic time of a hard spring is less as compared to that of a soft spring.
Reason: The periodic time depends upon the spring constant, which is large for hard spring.
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: It is not possible for a system, unaided by an external agency to transfer heat from a body at lower temperature to another body at a higher temperature.
Reason: It is not possible to violate the second law of thermodynamics
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: To hear distinct beats, difference in frequencies of two sources should be less than 10.
Reason: More the number of beats per sec
more difficult to hear them.
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.