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A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nm is U1, at wavelength 500 nm is U2 and that at 1000nm is U3. Wien’s constant, b = 2.88 × 10^6 nmK. Which of the following is correct?
31
Aug
A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nm is U1, at wavelength 500 nm is U2 and that at 1000nm is U3. Wien’s constant, b = 2.88 × 10^6 nmK. Which of the following is correct? A black body is at [...]
A pump is required to lift 1000kg of water per minute from a well 20m deep and eject it at a rate of 20m/s. a. How much work is done in lifting water? b. How much work is done in giving in KE? c. What HP(horsepower) engine is required for the purpose of lifting water?
31
Aug
A pump is required to lift 1000kg of water per minute from a well 20m deep and eject it at a rate of 20m/s. a. How much work is done in lifting water? b. How much work is done in giving in KE? c. What HP(horsepower) engine is required for the purpose of lifting water? [...]
Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at 100 C. While the other one is at 0 C. If the two bodies are brought into contact, then assuming no heat loss, the final common temperature is
31
Aug
Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at 100 C. While the other one is at 0 C. If the two bodies are brought into contact, then assuming no heat loss, the final common temperature is the final common temperature is then [...]
Certain quantity of water cools from 70C to 60C in the first 5 minutes and to 54C in the next 5 minutes. The temperature of the surroundings is
31
Aug
Certain quantity of water cools from 70C to 60C in the first 5 minutes and to 54C in the next 5 minutes. The temperature of the surroundings is Certain quantity of water cools from 70C to 60C in the first 5 minutes and to 54C in the next 5 minutes. The temperature of the surroundings [...]
An automobile of mass m accelerates, starting from rest, while the engine supplies constant power P, its position and instantaneous velocity changes w.r.t. time assuming the automobile starts from rest.
31
Aug
An automobile of mass m accelerates, starting from rest, while the engine supplies constant power P, its position and instantaneous velocity changes w.r.t. time assuming the automobile starts from rest. An automobile of mass m accelerates its position and instantaneous velocity changes w.r.t. time assuming the automobile starts from rest. starting from rest while the [...]
A car of mass 500 kg moving with speed 36 km/h in straight rod unidirectionally doubles its speed in one minute. find power delivered by engine
31
Aug
A car of mass 500 kg moving with speed 36 km/h in straight rod unidirectionally doubles its speed in one minute. find power delivered by engine A car of mass 500 kg moving with speed 36 km/h in straight rod unidirectionally doubles its speed in one minute. find power delivered by engine August 31, 2020 [...]
A small body of mass m is located on a horizontal plane at the point O. The body acquires a horizontal velocity v0. Find the mean power developed by the friction force during the whole time of motion, if the friction coefficient k = 0.27, m = 1.0kg, and v0 = 1.5m/s.
31
Aug
A small body of mass m is located on a horizontal plane at the point O. The body acquires a horizontal velocity v0. Find the mean power developed by the friction force during the whole time of motion, if the friction coefficient k = 0.27, m = 1.0kg, and v0 = 1.5m/s. A small body [...]
A body cools from a temperature 3T to 2T in 10 minutes. The room temperature is T. Assume that Newton’s law of cooling is applicable. The temperature of the body at the end of next 10 minutes will be
31
Aug
A body cools from a temperature 3T to 2T in 10 minutes. The room temperature is T. Assume that Newton’s law of cooling is applicable. The temperature of the body at the end of next 10 minutes will be A body cools from a temperature 3T to 2T in 10 minutes. The room temperature is [...]
On a new scale of temperature (which is linear) and called the W scale. The freezing and boiling points of water are 39 degree W and 239 degree W respectively. What will be the temperature on the new scale, corresponding to a temperature of 39 degree C on the Celsius scale?
31
Aug
On a new scale of temperature (which is linear) and called the W scale. The freezing and boiling points of water are 39 degree W and 239 degree W respectively. What will be the temperature on the new scale, corresponding to a temperature of 39 degree C on the Celsius scale? taking latent heat of [...]
Which of the following circular rods (given radius r and length l), each made of the same material and whose ends are maintained at the same temperature will conduct most heat?
31
Aug
Which of the following circular rods (given radius r and length l), each made of the same material and whose ends are maintained at the same temperature will conduct most heat? each made of the same material and whose ends are maintained at the same temperature will conduct most heat? Which of the following circular [...]