Physics 299 Questions Ask question Search Order By: ActiveCategoryClear Filter 1 Votes 1 Ans An iron ring of diameter 5.231 m is to be fixed on a wooden rim of diameter 5.243 m both initially at 270C. To what temperature should the iron ring be heated so as to fit the rim? (Coefficient of linear expansion of iron is 1.2× 10-5 k-1 ) 46 viewsAditya Bhatt Answered question 25 January 2024EducationPhysics 1 Votes 1 Ans A brass rod of length 50cm and diameter 3mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 2500C, if the original lengths are at 400C? Coefficient of linear expansion of brass and steel are 2.1 × 10-5 0C-1 and 1.2 × 10-5 0C-1 respectively 61 viewsAditya Bhatt Answered question 25 January 2024EducationPhysics 1 Votes 1 Ans a capacitor of 2uf is charged as shown in the diagram. When the switch S is turned to position 2, the percentage of its stored energy dissipated is 51 viewsAditya Bhatt Answered question 25 January 2024EducationPhysics 2 Votes 1 Ans A battery of 24 cells each of emf 1.5 V and internal resistance, 2Ω is to be connected in order to send the maximum current through a 12Ω resistor. How are they to be connected? Find the current in each cell and the potential difference across the external resistance. 41 viewsAditya Bhatt Changed status to publish 25 January 2024EducationPhysics 0 Votes 1 Ans A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500 °C and then placed on a large ice block. What is the maximum amount of ice that can melt? (Specific heat of copper = 0.39 J /g k; heat of fusion of water = 335 J/g) 48 viewsAditya Bhatt Changed status to publish 24 January 2024EducationPhysics 0 Votes 0 Ans Thermal properties of matter neet numerical 24 viewsMohd Ishaq Asked question 23 January 2024EducationPhysics 1 Votes 1 Ans A gram molecule of a gas at 127C expands isothermally until its volume is doubled. Find the amount of work done and heat absorbed. Take R= 8.31 J mole-1 K-1. 70 viewsAditya Bhatt Changed status to publish 23 January 2024EducationPhysics 1 Votes 1 Ans A large steel wheel is to be fitted onto a shaft of the same material. At 270C, the outer diameter of the shaft is 8.70cm and the diameter of the central hole in the wheel is 8.69cm. The shaft is cooled using dry ice. At what temperature of the shaft does the wheel slip on the shaft? Assume the coefficient of linear expansion of the steel to be constant over the required temperature range is 1.2 × 10-5 K-1? 47 viewsAditya Bhatt Changed status to publish 22 January 2024EducationPhysics 0 Votes 1 Ans A hole is drilled in a copper sheet. The diameter of the hole is 4.24cm at 270C. What is the change in the diameter of the hole when the sheet is heated to 2270C? The coefficient of linear expansion of copper is 1.7×10-5 0C-1 36 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 1 Votes 1 Ans What is the temperature of the steel-copper junction in the steady state of the system? Length of the steel rod = 15.0 cm; length of the copper rod = 10.0 cm, temperature of the furnace = 300°C, temperature of the other end = 0°C. The area of the cross-section of the steel rod is twice that of the copper rod. [Thermal conductivity of steel = 50.2 J/s m K; and for copper = 385 J/s m K]? 28 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans The coefficient of volume expansion of glycerin is 49 × 10-5 K-1. What is the fractional change in its density for a 300C rise in temperature? 41 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans The spectral energy distribution of the sun has a maximum of 4753 angstroms. If the temperature of the sun is 6050 K, what is the temperature of a star for which this maximum is at 9506 angstroms? 44 viewsAditya Bhatt Changed status to publish 22 January 2024EducationPhysics 0 Votes 1 Ans A brass wire 1.8m long at 270C is held taut with little tension between two rigid supports. If the wire is cooled to a temperature of -390C, what is the tension developed in the wire, if the diameter is 2.0 mm? Coefficient of linear expansion of brass = 2.0 × 10-5 0C-1, and Young’s modulus of brass = 0.91 × 1011 N/m2 38 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans A brass wire 1.8m long at 270C is held taut with little tension between two rigid supports. If the wire is cooled to a temperature of -390C, what is the tension developed in the wire, if the diameter is 2.0 mm? Coefficient of linear expansion of brass = 2.0 × 10-5 0C-1, and Young’s modulus of brass = 0.91 × 1011 N/m2 42 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans When 0.15kg of ice at 0C is mixed with 0.30 kg of water at 500C in a container, the resulting temperature is 6.70C. Calculate the heat of the fusion of ice.(SW= 4186 J kg-1 K-1) 47 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans A 10kW drilling machine is used to drill a bore in a small aluminum block of mass 8.0 kg. How much is the rise in temperature of the block in 2.5 minutes assuming 50% of power is used up in heating the machine itself or lost to the surrounding? Specific heat of aluminium = 0.91 Jg-1 0C-1 35 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans An electric heater supplies heat to a system at a rate of 100W. If the system performs work at a rate of 75 Joules per second. At what rate is the internal energy increasing? 44 viewsAditya Bhatt Answered question 22 January 2024EducationPhysics 0 Votes 1 Ans A Thermometer has the wrong calibration. read -10 C 52 viewsAditya Bhatt Answered question 21 January 2024EducationPhysics 1 Votes 1 Ans A certain gas at atmospheric pressure is compressed adiabatically so that its volume becomes half of its original volume. Calculate the resulting pressure in Nm-2. (γ=1.4) 54 viewsAditya Bhatt Answered question 20 January 2024EducationPhysics « Previous 1 2 … 13 14 15