Answer: D
Wavelength λ = 7.5 × 10^-11 m
Explanation:
You are given the frequency of an electromagnetic wave to be:
F = 4.0 x 1018 Hz. And the speed of light C to be
C = 3 × 10^8 m/s
From wave speed formula:
Wave speed is the product of waves frequency and wavelength. That is,
V = fλ
Where
f = frequency
λ = wavelength
V = C = speed of light
Substitute the values of the parameters into the formula
C = fλ
3 × 10^8 = 4 × 10^18 × λ
Make λ the subject of formula
λ = (3×10^8)/(4×10^18)
λ = 7.5 × 10^-11 m
Therefore, the wavelength of the wave is 7.5 × 10^-11 m
Answer:
Number of photons travel through pin hole=
Explanation:
First we will calculate the energy of single photon using below formula:
Where :
h is plank's constant with value 
c is the speed of light whch is
λ is the wave length = 532nm
E=
J
Number of photons emitted per second:
Number of photons emitted per second=
=
Where:
A-hole is area of hole
A-beam is area of beam
d-hole is diameter of hole
d-beam is diameter if beam
=
=
=
Number of photons travel through pin hole=
Number of photons travel through pin hole=
Answer:
it take 687 days for Mars orbit around the sun
Answer:
3) C
4 D
5) C
Explanation:
3) given that
Initial distance of the screen = 100cm
Initial area = 150 cm^2
Final distance = 200 cm
The intensity of light is inversely proportional to the square of the distance. That is
Intensity of light I = 1/d2
And also I = P/A
1/d^2 = P/A
P = A/d^2
P1 = P2
150/100 = A/200
1.5 = A/200
A = 1.5 × 200
A = 300 cm^2
4.) Light is projected onto a screen 75.0 cm from a light source. The light intensity = 4436 lux
If the screen is moved from 75.0 cm to 150. cm, the light sensor reading will be
Using inverse square law
I = 1/d^2
I×d^2 = constant. Therefore,
4436 × 75^2 = I × 150^2
I = 24952500/22500
I = 1109 lux
5.) We can express the relationship between luminosity, brightness, and distance with a simple formula.
As we tilt the serene the area of light decreases and makes the light more concentrated.
The artic tundra can be found in D. All of the above.
