1. A student performing Young's experiment with a single-colour source finds the distance between the rst and the seventh nodal lines to be 6.0 cm.The screen is located 3.0 m from the two slits. The slit separation is 2.2 x it]2 pm. Calculate the wavelength of the light. 2. Single-colour light falling on two slits 0.042 mm apart produces the fth-order fringe at a 3.8 angle. Calculate the wavelength of the light. 3. An interference pattern is ionned on a screen when helium-neon laser light (it. =- 6.3 x In" rn) is directed toward it through two slits. The slits are 43 pm apart. The screen is 2.5 m away. Calculate the separation of adjacent nodal lines