NEET Physics Thermal Properties Of Matter Class 11 Questions

A steel rail of length 5 m and area of cross section 40 cm² is prevented from expanding along its length while the temperature rises by 10°C. If coefficient of linear expansion and Young's modulus of steel are 1.2 × 10⁻⁵ K⁻¹ and 2 × 10¹¹ Nm⁻² respectively, the force developed in the rail is approximately:

The stress-strain graph for a metal wire is as shown in the figure. In the graph, the region in which elasticity is maintained the ultimate strength and fracture points are represented by

The volume thermal expansion coefficient of an ideal gas at constant pressure is directly proportional to (Here T = absolute temperature of gas)

With increase in temperature, the viscosity of

A square lead slab of side 50 cm and thickness 10 cm is subjected to a shearing force (on its narrow face) of 9 × 10⁴ N. The lower edge is riveted to the floor. How much will the upper edge be displaced? (Shear modulus of lead = 5.6 × 10⁹ N m⁻²)

The ratio of excess pressure inside a soap bubble to the excess of pressure inside an air bubble in a soap solution is

Two wires A and B made of different materials of lengths 6.0 cm and 5.4 cm, respectively and area of cross sections 3.0 × 10⁻⁵ m² and 4.5 × 10⁻⁵ m², respectively are stretched by the same magnitude under a given load. The ratio of the Young's modulus of A to that of B is x : 3. The value of x is

What is the excess pressure inside a bubble of soap solution of radius 5.00 mm, given that the surface tension of soap solution at 20°C is 2.50 × 10⁻² Nm⁻¹?

Density of substance at 0°C is 10 gm/cc and at 100°C, its density is 9.7 gm/cc. The coefficient of linear expansion of the substance will be

Four rods of same material with different radii r and length are used to connect two reservoirs of heat at different temperatures. Which one will conduct most heat?

Three identical heat conducting rods are connected in series as shown in the figure. The rods on the sides have thermal conductivity 2K while that in the middle has thermal conductivity K. The left end of the combination is maintained at temperature 3T and the right end at T. The rods are thermally insulated from outside. In steady state, temperature at the left junction is T₁ and that at the right junction is T₂. The ratio T₁/T₂ is

A metallic bar of Young’s modulus, 0.5 × 10¹¹ N m⁻² and coefficient of linear thermal expansion 10⁻⁵ °C⁻¹, length 1 m and area of cross-section 10⁻³ m² is heated from 0°C to 100°C without expansion or bending. The compressive force developed in it is:

A cup of coffee cools from 90°C to 80°C in t minutes, when the room temperature is 20°C. The time taken by a similar cup of coffee to cool from 80°C to 60°C at a room temperature same at 20°C is :

The quantities of heat required to raise the temperature of two solid copper spheres of radii r₁ and r₂ (r₁ = 1.5 r₂) through 1 K are in the ratio:

The unit of thermal conductivity is:

A copper rod of 88 cm and an aluminum rod of unknown length have their increase in length independent of increase in temperature. The length of aluminum rod is: (αCu = 1.7 × 10⁻⁵ K⁻¹ and αAl = 2.2 × 10⁻⁵ K⁻¹)

The power radiated by a black body is P and it radiates maximum energy at wavelength λ₀. If the temperature of the black body is now changed so that it radiates maximum energy at wavelength 3/4 λ₀, the power radiated by it becomes nP. The value of n is

The bulk modulus of a spherical object is ‘B’. If it is subjected to uniform pressure ‘P’, the fractional decrease in radius is

Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are K₁ and K₂. The thermal conductivity of the composite rod will be

A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be:

Coefficient of linear expansion of brass and steel rods are α1 and α2. Lengths of brass and steel rods are l¹ and l² respectively. If (l² − l¹) is maintained same at all temperatures, which one of the following relations holds good?

A piece of ice falls from a height h so that it melts completely. Only one – quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is (Latent heat of ice is 3.4 × 10⁵ J/kg and g = 10 N/kg)

On observing light from three different stars P, Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If T_P, T_Q and T_R are the respective absolute temperatures of P, Q and R then it can be concluded from the above observations that

The two ends of a metal rod are maintained at temperatures 100°C and 110°C. The rate of heat flow in the rod is found to be 4.0 J/s. If the ends are maintained at temperatures 200°C and 210°C, the rate of heat flow will be

Certain quantity of water cools from 70 °C to 60 °C in the first 5 minutes and to 54 °C in the next 5 minutes. The temperature of the surroundings is

Two metal rods 1 and 2 of same lengths have same temperature difference between their ends. Their thermal conductivities are K₁ and K₂, and cross sectional areas A₁ and A₂, respectively. If the rate of the heat conduction in 1 is four times that in 2, then:

The density of water at 20°C is 998 kg/m³ and at 40°C is 992 kg/m³. The coefficient of volume expansion of water is: