Physics-
General
Easy

Question

A lamp rated at 100 cd hangs over the middle of a round table with diameter 3 m at a height of 2 m. It is replaced by a lamp of 25 cd and the distance to the table is changed so that the illumination at the centre of the table remains as before. The illumination at edge of the table becomes X times the original. Then X is

  1. fraction numerator 1 over denominator 3 end fraction    
  2. fraction numerator 16 over denominator 27 end fraction    
  3. fraction numerator 1 over denominator 4 end fraction    
  4. fraction numerator 1 over denominator 9 end fraction    

The correct answer is: fraction numerator 1 over denominator 3 end fraction

Related Questions to study

General
physics-

Five lumen/watt is the luminous efficiency of a lamp and its luminous intensity is 35 candela. The power of the lamp is

Five lumen/watt is the luminous efficiency of a lamp and its luminous intensity is 35 candela. The power of the lamp is

physics-General
General
physics-

Lux is equal to

Lux is equal to

physics-General
General
physics-

A 60 watt bulb is hung over the center of a table 4 m cross times 4 m at a height of 3 m. The ratio of the intensities of illumination at a point on the centre of the edge and on the corner of the table is

A 60 watt bulb is hung over the center of a table 4 m cross times 4 m at a height of 3 m. The ratio of the intensities of illumination at a point on the centre of the edge and on the corner of the table is

physics-General
parallel
General
maths-

If f(x) is a polynomial of degree five with leading coefficient one such that  f(1)=12,f(2)=22,f(3)=32,f(4)=42,f(5)=52 then

If f(x) is a polynomial of degree five with leading coefficient one such that  f(1)=12,f(2)=22,f(3)=32,f(4)=42,f(5)=52 then

maths-General
General
maths-

If f(x) = ax2+ bx + c such that f(p) + f(q) = 0 where anot equal to0 ; p , qelement ofR then number of real roots of equation f(x) = 0in interval [p, q] is

If f(x) = ax2+ bx + c such that f(p) + f(q) = 0 where anot equal to0 ; p , qelement ofR then number of real roots of equation f(x) = 0in interval [p, q] is

maths-General
General
maths-

If f(x) is a differentiable function satisfying f(x+ y)= f(x)f(y) straight for all x, y element of R and f'(0)=2 then f(x)=

If f(x) is a differentiable function satisfying f(x+ y)= f(x)f(y) straight for all x, y element of R and f'(0)=2 then f(x)=

maths-General
parallel
General
physics-

Maximum kinetic energy (Ek ) of a photoelectron varies with the frequency ( v ) of the incident radiation as

Maximum kinetic energy (Ek ) of a photoelectron varies with the frequency ( v ) of the incident radiation as

physics-General
General
maths-

The degree of the differential equation satisfying square root of 1 plus x squared end root plus square root of 1 plus y squared end root equals A open parentheses x square root of 1 plus y squared end root minus y square root of 1 plus x squared end root close parentheses is

The degree of the differential equation satisfying square root of 1 plus x squared end root plus square root of 1 plus y squared end root equals A open parentheses x square root of 1 plus y squared end root minus y square root of 1 plus x squared end root close parentheses is

maths-General
General
Maths-

If x fraction numerator d y over denominator d x end fraction equals y left parenthesis log space y minus log space x plus 1 right parenthesis then the solution of the equation is :

If x fraction numerator d y over denominator d x end fraction equals y left parenthesis log space y minus log space x plus 1 right parenthesis then the solution of the equation is :

Maths-General
parallel
General
physics-

A simple magnifying lens is used in such a way that an image is formed at 25 cm away from the eye. In order to have 10 times magnification, the focal length of the lens should be

A simple magnifying lens is used in such a way that an image is formed at 25 cm away from the eye. In order to have 10 times magnification, the focal length of the lens should be

physics-General
General
Maths-

The differential equation of all circles which pass through the origin and whose centres lie on y-axis is

The differential equation of all circles which pass through the origin and whose centres lie on y-axis is

Maths-General
General
maths-

Let p, qelement of{1,2,3,4}.Then number of equation of the form px2+qx+1=0,having real roots ,is

Let p, qelement of{1,2,3,4}.Then number of equation of the form px2+qx+1=0,having real roots ,is

maths-General
parallel
General
maths-

Number of values of 'p' for which the equationopen parentheses p squared minus 3 p plus 2 close parentheses x squared minus open parentheses p squared minus 5 p plus 4 close parentheses x plus p minus p squared equals 0 possess more  than two roots ,is:

Number of values of 'p' for which the equationopen parentheses p squared minus 3 p plus 2 close parentheses x squared minus open parentheses p squared minus 5 p plus 4 close parentheses x plus p minus p squared equals 0 possess more  than two roots ,is:

maths-General
General
maths-

Statement-1- The number blank to the power of 1000 end exponent C subscript 500 end subscript is not divisible by 11.Because
Statement-2- If p is a prime, the exponent of p in n! is open square brackets fraction numerator n over denominator p end fraction close square brackets+ open square brackets fraction numerator n over denominator p to the power of 2 end exponent end fraction close square brackets+ open square brackets fraction numerator n over denominator p to the power of 3 end exponent end fraction close square brackets+……Where [x] denotes the greatest integer less or equal than x.

Statement-1- The number blank to the power of 1000 end exponent C subscript 500 end subscript is not divisible by 11.Because
Statement-2- If p is a prime, the exponent of p in n! is open square brackets fraction numerator n over denominator p end fraction close square brackets+ open square brackets fraction numerator n over denominator p to the power of 2 end exponent end fraction close square brackets+ open square brackets fraction numerator n over denominator p to the power of 3 end exponent end fraction close square brackets+……Where [x] denotes the greatest integer less or equal than x.

maths-General
General
physics-

According to Newton’s law of cooling, the rate of cooling is proportional to open parentheses increment theta close parentheses to the power of n end exponent, where increment theta is the temperature differences between the body and the surroundings andn is equal to

According to Newton’s law of cooling, the rate of cooling is proportional to open parentheses increment theta close parentheses to the power of n end exponent, where increment theta is the temperature differences between the body and the surroundings andn is equal to

physics-General
parallel

card img

With Turito Academy.

card img

With Turito Foundation.

card img

Get an Expert Advice From Turito.

Turito Academy

card img

With Turito Academy.

Test Prep

card img

With Turito Foundation.