Thermal Properties Of Matter CBSE Questions & Answers

A brass spring has a spring constant k. When the spring is heated, the spring constant will

Which of the following statement(s) is/are true?(I) Every substance contains heat. (II) For heat to flow between two substances, they must be at different temperatures. (III) The internal energy of a substance is equal to the kinetic energy of the molecules in the substance.

A washer consists of a 3.00 cm diameter circle of sheet metal with a 1.00 cm diameter circular hole in the middle. If the metal washer is heated until the diameter of the washer is 3.03 cm, then the diameter of the hole will be

Find the wrong statement about specific heat of a material

Molar Specific Heat capacity has units of

thermal conductivity has units of

The triple points of neon is 24.57 K. Express this temperatures on the Celsius and Fahrenheit scales

The triple points of carbon dioxide is 216.55 K. Express this temperatures on the Celsius and Fahrenheit scales

Two absolute scales A and B have triple points of water defined to be 200 A and 350 B. What is the relation between \({{\rm{T}}_{\rm{A}}}\) and \({{\rm{T}}_{\rm{B}}}\) ?

The electrical resistance in ohms of a certain thermometer varies with temperature according to the approximate law : R = R\(_{\rm{o}}\) [1 + \(\alpha \) (T – T\(_{\rm{o}}\) )] The resistance is 101.6 \(\Omega \) at the triple-point of water 273.16 K, and 165.5 \(\Omega \) at the normal melting point of lead (600.5 K). What is the temperature when the resistance is 123.4 \(\Omega \)?

A steel tape 1m long is correctly calibrated for a temperature of 27.0 \(^\circ \)C. The length of a steel rod measured by this tape is found to be 63.0 cm on a hot day when the temperature is 45.0 \(^\circ \)C. What is the actual length of the steel rod on that day? Coefficient of linear expansion of steel = 1.20 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) \({{\rm{K}}^{-{\rm{1}}}}\)

A large steel wheel is to be fitted on to a shaft of the same material. At 27 \(^\circ \)C, the outer diameter of the shaft is 8.70 cm and the diameter of the central hole in the wheel is 8.69 cm. The shaft is cooled using ‘dry ice’. At what temperature of the shaft does the wheel slip on the shaft? Assume coefficient of linear expansion of the steel to be constant over the required temperature range: \({\alpha _{{\rm{steel}}}}\) = 1.20 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) \({{\rm{K}}^{-{\rm{1}}}}\).

A hole is drilled in a copper sheet. The diameter of the hole is 4.24 cm at 27.0 \(^\circ \)C. What is the change in the diameter of the hole when the sheet is heated to 227 \(^\circ \)C? Coefficient of linear expansion of copper = 1.70 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) K–1.

A brass wire 1.8 m long at 27 \(^\circ \)C is held taut with little tension between two rigid supports. If the wire is cooled to a temperature of –39 \(^\circ \)C, what is the tension developed in the wire, if its diameter is 2.0 mm? Co-efficient of linear expansion of brass = 2.0 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) \({{\rm{K}}^{-{\rm{1}}}}\); Young’s modulus of brass = 0.91 \( \times \) \({\rm{1}}{0^{{\rm{11}}}}\) Pa.

A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 250 \(^\circ \)C, if the original lengths are at 40.0 \(^\circ \)C? The ends of the rod are free to expand (Co-efficient of linear expansion of brass = 2.0 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) \({{\text{K}}^{--{\text{1}}}}\), steel = 1.2 \( \times \) \({\rm{1}}{0^{-{\rm{5}}}}\) \({{\text{K}}^{--{\text{1}}}}\)).