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A short pulse of white light is incident from air to a glass slab at normal incidence. After traveling through the slab, the first colour to emerge is
19
Nov
A short pulse of white light is incident from air to a glass slab at normal incidence. After traveling through the slab, the first colour to emerge is A short pulse of white light is incident from air to a glass slab at normal incidence. After traveling through the slab the first colour to emerge [...]
The near vision of an average person is 25cm. To view an object with an angular magnification of 10, what should be the power of the microscope ?
19
Nov
The near vision of an average person is 25cm. To view an object with an angular magnification of 10, what should be the power of the microscope ? The near vision of an average person is 25cm. To view an object with an angular magnification of 10 what should be the power of the microscope [...]
Will the focal length of a lens for red light be more, same or less than that for blue light ?
19
Nov
Will the focal length of a lens for red light be more, same or less than that for blue light ? same or less than that for blue light ? Will the focal length of a lens for red light be more November 19, 2020 Category: Chapter 9 - Ray Optics and Optical Instruments , [...]
A car is moving with a constant speed of 60kmh^−1 on a straight road. Looking at the rear view mirror, the driver finds that the car following him is at a distance of 100m and is approaching with a speed of 5kmh^−1. In order to keep track of the car in the rear, the driver begins to glance alternatively at the rear and side mirror of his car after every 2s till the other car overtakes. If the two cars were maintaining their speeds, which of the following statement (s) is/are correct ?
19
Nov
A car is moving with a constant speed of 60kmh^−1 on a straight road. Looking at the rear view mirror, the driver finds that the car following him is at a distance of 100m and is approaching with a speed of 5kmh^−1. In order to keep track of the car in the rear, the driver [...]
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A car is moving with a constant speed of 60kmh^−1 on a straight road. Looking at the rear view mirror ,
the driver begins to glance alternatively at the rear and side mirror of his car after every 2s till the other car overtakes. If the two cars were maintaining their speeds ,
the driver finds that the car following him is at a distance of 100m and is approaching with a speed of 5kmh^−1. In order to keep track of the car in the rear ,
which of the following statement (s) is/are correct ? ,
The direction of a ray of light incident on a concave mirror is shown by PQ while directions in which the ray would travel after reflection is shown by four rays marked 1,2,3 and 4. Which of the four rays correctly shows the direction of reflected ray ?
19
Nov
The direction of a ray of light incident on a concave mirror is shown by PQ while directions in which the ray would travel after reflection is shown by four rays marked 1,2,3 and 4. Which of the four rays correctly shows the direction of reflected ray ? 2 3 and 4. Which of the [...]
Two black bodies at temperatures 327ºC and 427ºC are kept in an evacuated chamber at 27ºC. The ratio of their rates of loss of heat are :
19
Nov
Two black bodies at temperatures 327ºC and 427ºC are kept in an evacuated chamber at 27ºC. The ratio of their rates of loss of heat are : Two black bodies at temperatures 327ºC and 427ºC are kept in an evacuated chamber at 27ºC. The ratio of their rates of loss of heat are : November [...]
The maximum spectral emissive power of a black body at a temperature of 5000 K is obtained as λm = 6000 Å. If the temperature is increased by 10%, then the decrease in λm will be
19
Nov
The maximum spectral emissive power of a black body at a temperature of 5000 K is obtained as λm = 6000 Å. If the temperature is increased by 10%, then the decrease in λm will be The maximum spectral emissive power of a black body at a temperature of 5000 K is obtained as λm [...]
Three stars A,B,C have surface temperatures TA,TB and TC. A appears bluish, B appears reddish and C appears yellowish. We can conclude that
19
Nov
Three stars A,B,C have surface temperatures TA,TB and TC. A appears bluish, B appears reddish and C appears yellowish. We can conclude that B B appears reddish and C appears yellowish. We can conclude that C have surface temperatures TA TB and TC. A appears bluish Three stars A November 19, 2020 Category: Chapter 16 [...]
The surface temperature of the sun which has maximum energy emission at 500 nm is 6000 K. The temperature of star which has maximum energy emission at 400 nm will be.
19
Nov
The surface temperature of the sun which has maximum energy emission at 500 nm is 6000 K. The temperature of star which has maximum energy emission at 400 nm will be. The surface temperature of the sun which has maximum energy emission at 500 nm is 6000 K. The temperature of star which has maximum [...]
The maximum energy is the thermal radiation from a hot source occurs at a wavelength of 11×10^−5cm. According to Wien’s law, the temperature of the source (on Kelvin scale) for which the wavelength at mixture energy is 5.5×10^−5 cm. The value of n is:
19
Nov
The maximum energy is the thermal radiation from a hot source occurs at a wavelength of 11×10^−5cm. According to Wien’s law, the temperature of the source (on Kelvin scale) for which the wavelength at mixture energy is 5.5×10^−5 cm. The value of n is: The maximum energy is the thermal radiation from a hot source [...]