True or false- the number of bright bands per unit length observed in an interference pattern on a screen, will increase when the wavelength of the waves passing through a double slit increases- if ur kind enough plz xplain it 2me
To determine if the number of bright bands per unit length observed in an interference pattern on a screen increases when the wavelength of the waves passing through a double slit increases, we need to understand the concept of interference and the factors that influence it.
Interference occurs when two or more waves interact with each other. In the case of a double slit interference pattern, a beam of light passes through two parallel slits, and the light waves diffract as they pass through each slit. The diffracted waves then overlap and interfere with each other, creating a pattern of alternating bright and dark bands on a screen placed in the path of the diffracted light.
The key factors that influence the interference pattern in a double-slit experiment are the distance between the slits (d), the distance from the slits to the screen (L), and the wavelength of the light waves (λ). These factors are related to the pattern observed on the screen, including the number of bright bands per unit length.
When the wavelength of the waves passing through the double slits increases:
1. The distance between successive bright bands (called the fringe spacing or fringe width) will increase.
2. The overall size of the pattern (the distance from the central bright band to the outermost bands) remains the same.
The fringe spacing is given by the formula: fringe spacing = λL/d. Therefore, increasing the wavelength (λ) of the waves passing through the double slits while keeping the other parameters constant, will cause an increase in the fringe spacing. This means that the number of bright bands per unit length observed in the interference pattern will decrease because the bright bands become further apart.
In conclusion, the statement is false. The number of bright bands per unit length observed in an interference pattern on a screen will decrease, not increase, when the wavelength of the waves passing through a double slit increases.