A Single and A Double Slit Question

[zmike]

Two questions (I've got my AP Physics exam tmr :S)

1. What is the angular width of the the central maximum produced by a single slit of width 0.0011 cm if illuminated by blue light of a wavelength of 470 nm.

So I used Sin () = (m+0.5) lamda/w


2. What is the max. number of bright spots when red light is shone on a pair of double slits 1.4 mm apart when the screen is 1.0 away.

I think you would use since()m = m(lamda/d) but I get this werid decimal number and you can't have a decimal number of bright spots.


thanks in advanced

 

[zmike]

help please, my exam is tmr morning :( please

 

[Moetasim]

1. To calculate the angular width of the central maximum produced by a single slit, we can use the equation Sin(θ) = (m + 0.5)λ/w, where θ is the angular width, m is the order of the maximum, λ is the wavelength of the light, and w is the width of the slit. Plugging in the given values, we get Sin(θ) = (0 + 0.5)(470 nm)/(0.0011 cm). Solving for θ, we get an angular width of approximately 0.214 degrees.

2. The max number of bright spots in a double slit experiment can be calculated using the equation m = m(λ/d), where m is the number of bright spots, λ is the wavelength of the light, and d is the distance between the slits. In this case, we have a distance of 1.4 mm between the slits and a wavelength of red light (around 700 nm). Plugging in these values, we get m = (700 nm)/(1.4 mm) = 0.5. This means that there will be a maximum of 0.5 bright spots, which is not possible. This could be due to rounding errors or limitations of the equation, but it is important to remember that this is a theoretical maximum and in reality, the number of bright spots may be slightly different.