Question
An electric lamp is fixed at the ceiling of a circular tunnel as shown is figure. What is the ratio the intensities of light at base A and a point B on the wall
- 1 : 2
The correct answer is:
and 
Related Questions to study
The distance between a point source of light and a screen which is 60 cm is increased to 180 cm. The intensity on the screen as compared with the original intensity will be
The distance between a point source of light and a screen which is 60 cm is increased to 180 cm. The intensity on the screen as compared with the original intensity will be
The pole of the straight line 9x + y – 28 = 0 with respect to the circle 
is
Pole and polar are one of the important parts of the circle, many questions can be based on these parts. It should be remembered that while writing the equation of polar for a pole, the coefficients of square terms in the equation of the circle is one. If the equation of the circle does not have coefficients as one, then make it one before solving the question.
The pole of the straight line 9x + y – 28 = 0 with respect to the circle is
Pole and polar are one of the important parts of the circle, many questions can be based on these parts. It should be remembered that while writing the equation of polar for a pole, the coefficients of square terms in the equation of the circle is one. If the equation of the circle does not have coefficients as one, then make it one before solving the question.
Three rods of equal length 
are joined to form an equilateral triangle 
O is the mid point of 
Distance 
remains same for small change in temperature. Coefficient of linear expansion for 
and 
is same, 
but that for 
is 
Then
Three rods of equal length are joined to form an equilateral triangle O is the mid point of Distance remains same for small change in temperature. Coefficient of linear expansion for and is same, but that for is Then
A point source causes photoelectric effect from a small metal plate Which of the following curves may represent the saturation photocurrent as a function of the distance between the source and the metal?
A point source causes photoelectric effect from a small metal plate Which of the following curves may represent the saturation photocurrent as a function of the distance between the source and the metal?
One of the following figures respesents the variation of particle momentum with associated de Broglie wavelength
a) 
b) 
c) 
One of the following figures respesents the variation of particle momentum with associated de Broglie wavelength
a)
b)
c)
Two circular discs A and B with equal radii are blackened. They are heated to some temperature and are cooled under identical conditions. What inference do you draw from their cooling curves?
Two circular discs A and B with equal radii are blackened. They are heated to some temperature and are cooled under identical conditions. What inference do you draw from their cooling curves?
Which of the curves in figure represents the relation between Celsius and Fahrenheit temperatures
Which of the curves in figure represents the relation between Celsius and Fahrenheit temperatures
The area of circle centred at (1, 2) and passing through (4, 6) is
The area of a circle is the space occupied by the circle in a two-dimensional plane. Area of circle = πr2 (π = 22/7).
The area of circle centred at (1, 2) and passing through (4, 6) is
The area of a circle is the space occupied by the circle in a two-dimensional plane. Area of circle = πr2 (π = 22/7).
Three rods of same dimensions are arranged as shown in figure. They have thermal conductivities 
and 
. The points 
and 
are maintained at different temperatures for the heat to flow at the same rate along 
and then which of the following options is correct
Three rods of same dimensions are arranged as shown in figure. They have thermal conductivities and . The points and are maintained at different temperatures for the heat to flow at the same rate along and then which of the following options is correct
In the following diagram if 
then 
In the following diagram if then
The maximum kinetic energy (Ek ) of emitted photoelectrons against frequency v of incident radiation is plotted as shown in fig The slope of the graph is equal to
The maximum kinetic energy (Ek ) of emitted photoelectrons against frequency v of incident radiation is plotted as shown in fig The slope of the graph is equal to
In centre of the triangle formed by the lines y = x, y = 3x and y = 8 – 3x is
In centre of the triangle formed by the lines y = x, y = 3x and y = 8 – 3x is
