In a Young's Double Slit experiment, the separation of four bright fringes is 2.5mm, the wavelength of light used is 6.2*10^-7m. If the distance from the slits to the screen is 80cm, calculate the separation of two slits.
I applied
4*¥D/d=1.5*10^-3m
but the answer didn't match. It matches when I use 3¥D/d instead of 4.
Shouldn't the separation of four bright fringes be 4¥D/d (after applying sin@=tan@ approximation)
0 to 1
0 to -1
1 to 2
-1 to -2
that is three gaps
Yes, in the Young's Double Slit experiment, the separation of four bright fringes should be 4λD/d, where λ is the wavelength of light, D is the distance from the slits to the screen, and d is the separation of the slits.
Let's use the given values to calculate the separation of the slits:
Separation of four bright fringes (4λD/d) = 2.5 mm = 2.5 * 10^-3 m
Wavelength of light (λ) = 6.2 * 10^-7 m
Distance from slits to screen (D) = 80 cm = 80 * 0.01 m = 0.8 m
Now, we can rearrange the formula to solve for d:
4λD/d = 2.5 * 10^-3 m
d = 4λD / (2.5 * 10^-3 m)
Substituting the given values:
d = (4 * 6.2 * 10^-7 m * 0.8 m) / (2.5 * 10^-3 m)
d ≈ 9.984 * 10^-5 m
So, the separation of the two slits is approximately 9.984 * 10^-5 m.
To calculate the separation of the two slits in a Young's Double Slit experiment, you need to use the formula:
λ = (m * d) / D
Where:
λ is the wavelength of light used,
m is the order of the bright fringe,
d is the separation of the slits, and
D is the distance from the slits to the screen.
In your case, the separation of four bright fringes is given as 2.5 mm, which means that m = 4. The wavelength of light used is 6.2 * 10^-7 m, and the distance from the slits to the screen is 80 cm (or 0.8 m).
Using the formula mentioned above, you can rearrange it to find the separation of the slits (d):
d = (λ * D) / m
Substituting the values, we have:
d = (6.2 * 10^-7 * 0.8) / 4
Calculating this will give you the correct result for the separation of the two slits.