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Two bodies A and B have thermal emissivities of 0.01 and 0.81 respectively. The outer surface areas of the two bodies are same. The two bodies emit total radiant power at the same rate. The wavelength λB corresponding to maximum spectral radiancy from B is shifted from the wavelength corresponding to maximum spectral radiancy in the radiation from A by 1.0 μm. If the temperature of A is 5802 K, calculate (a) the temperature
02
Sep
Two bodies A and B have thermal emissivities of 0.01 and 0.81 respectively. The outer surface areas of the two bodies are same. The two bodies emit total radiant power at the same rate. The wavelength λB corresponding to maximum spectral radiancy from B is shifted from the wavelength corresponding to maximum spectral radiancy in [...]
If the filament of 100 w bulb has an are 0.25 cm^2 and behaves as a perfect black body. Find the wavelength corresponding to the maximum in its energy distribution. Given that Stefan’s constant is
02
Sep
If the filament of 100 w bulb has an are 0.25 cm^2 and behaves as a perfect black body. Find the wavelength corresponding to the maximum in its energy distribution. Given that Stefan’s constant is If the filament of 100 w bulb has an are 0.25 cm^2 and behaves as a perfect black body. Find [...]
Two capacitors A and B with capacities 3μF and 2μF are charged to a potential difference of 100V and 180V, respectively. The plates of the capacitors are connected as show in figure with one wire of each capacitor free. The upper plate of A is positive and that of B is negastive. An uncharged 2μF capcitor C with lead wires falls on the free ends to complete the circuit. Calculate a. the final charge on the three capacitors. b. the amount of electrostatic energy stored in the system before and after completion of the circuit.
02
Sep
Two capacitors A and B with capacities 3μF and 2μF are charged to a potential difference of 100V and 180V, respectively. The plates of the capacitors are connected as show in figure with one wire of each capacitor free. The upper plate of A is positive and that of B is negastive. An uncharged 2μF [...]
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A body cools from 60∘C to 50∘C in 10 minutes . If the room temperature is 25∘C and assuming Newton's law of cooling to hold good ,
Five identical conducting plates ,
the temperature of the body at the end of the next 10 minutes will be ,
Two capacitors A and B with capacities 3μF and 2μF are charged to a potential difference of 100V and 180V ,
The spectral energy distribution of the sun has a maximum at 4754Å. If the temperature of the sun is 6050 K, what is the temperature of a star for which this maximum is at 9506Å?
02
Sep
The spectral energy distribution of the sun has a maximum at 4754Å. If the temperature of the sun is 6050 K, what is the temperature of a star for which this maximum is at 9506Å? The spectral energy distribution of the sun has a maximum at 4754Å. If the temperature of the sun is 6050 [...]
Two parallel plate capacitors A and B have the same separation d = 8.85×10^−4 m between the plates. The plate area of A and B are 0.04 m^2 and 0.02 m^2 respectively. A slab of dielectric constant (relative permittivity) K = 9 has dimensions such that it can exactly fill the space between the plates of capacitor B. (i) The dielectric slab is placed inside. A as shown in figure (a). A is then charged to a potential difference of 110V. Calculate the capacitance of A and the energy stored in it. The battery is disconnected and then the dielectric slab is moved from A. Find the work done by the external agency in removing the slab from A. (iii) The same dielectric slab is now placed inside B, filling it completely, The two capacitors A and B are then connected as shown in figure(c). Calculate the energy stored in the system.
02
Sep
Two parallel plate capacitors A and B have the same separation d = 8.85×10^−4 m between the plates. The plate area of A and B are 0.04 m^2 and 0.02 m^2 respectively. A slab of dielectric constant (relative permittivity) K = 9 has dimensions such that it can exactly fill the space between the plates [...]
A hot black body emits the energy at the rate of 16 Jm^−2s^−1 and its most intense radiation corresponds to 20000Å. When the temprerature of this body is further increased and its most intense radiation corresponds to 10000Å, then find the value of energy radiated in Jm^−2s^−1.
02
Sep
A hot black body emits the energy at the rate of 16 Jm^−2s^−1 and its most intense radiation corresponds to 20000Å. When the temprerature of this body is further increased and its most intense radiation corresponds to 10000Å, then find the value of energy radiated in Jm^−2s^−1. A hot body placed in air is cooled [...]
Five identical conducting plates, 1,2,3,4 and 5 are fixed parallel pltes equidistant from each other (see figure). A conductor connects plates 2 and 5 while another conductor joins 1 and 3. The junction of 1 and 3 and the plate 4 are connected to a source of constant emf V0. Find (a) the effective capacity of the system between the terminals of source. (b) the charges on the plates 3 and 5. Given, d= distance between any two successive plates and A= area of either face of each plate.
02
Sep
Five identical conducting plates, 1,2,3,4 and 5 are fixed parallel pltes equidistant from each other (see figure). A conductor connects plates 2 and 5 while another conductor joins 1 and 3. The junction of 1 and 3 and the plate 4 are connected to a source of constant emf V0. Find (a) the effective capacity [...]
A hot body placed in air is cooled down according to Newton’s law of cooling, the rate of decrease of temperature being k times the temperature difference from the surrounding. Starting from t=0 , find the time in which the body will loss half the maximum heat it can lose.
02
Sep
A hot body placed in air is cooled down according to Newton’s law of cooling, the rate of decrease of temperature being k times the temperature difference from the surrounding. Starting from t=0 , find the time in which the body will loss half the maximum heat it can lose. A hot body placed in [...]
A body cools from 60∘C to 50∘C in 10 minutes . If the room temperature is 25∘C and assuming Newton’s law of cooling to hold good, the temperature of the body at the end of the next 10 minutes will be
02
Sep
A body cools from 60∘C to 50∘C in 10 minutes . If the room temperature is 25∘C and assuming Newton’s law of cooling to hold good, the temperature of the body at the end of the next 10 minutes will be A body cools from 60∘C to 50∘C in 10 minutes . If the room [...]
A body cools down from 60%=C to 55C in 30 s. Using newton’s law of cooling calculate the time taken by same body to cool down from 55C to 50C. Assume that the temperature of surrounding is 45C.
02
Sep
A body cools down from 60%=C to 55C in 30 s. Using newton’s law of cooling calculate the time taken by same body to cool down from 55C to 50C. Assume that the temperature of surrounding is 45C. A body cools down from 60%=C to 55C in 30 s. Using newton's law of cooling calculate [...]