2022 RI Promo Sect C QP

© Raffles Institution [Turn over Name: ( ) CT Group: 23S0 RAFFLES INSTITUTION 2022 YEAR 5 PROMOTION EXAMINATION 30 September 2022 H2 PHYSICS RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION I Section C INSTRUCTIONS TO CANDIDATES Write your name, index number and CT Group. Write your answers to Section C in the spaces provided in this booklet. For Examiner’s Use Section C 21 / 15 22 / 15 There are 10 printed pages, inclusive of the cover page, in this booklet

2 © Raffles Institution 21 (a) In an experiment to demonstrate the double-slit interference pattern, parallel light of wavelength 589.0 nm from a sodium lamp is incident on a pair of slits S 1 and S 2 each of width 0.150 mm and separated by 0.450 mm. The interference pattern is observed at a screen located 2.000 m away from the slits as illustrated in Fig. 21.1. Fig. 21.1 (not to scale) At the start of the experiment, an opaque obstacle was carefully positioned in front of the double-slit system such that only the light passing through S 1 is incident on the screen. Determine the distance of the first minimum from the centre of the central bright fringe. distance = m [3] (b) The opaque obstacle is now removed so that an interference pattern is observed. (i) Determine the separation between two nei ghbouring fringes of the interference pattern. frin ge separation = m [2] 0.150 mm 0.450 mm S1 S2 yellow light (589.0 nm) opaque obstacle screen 2.000 m

3 © Raffles Institution [Turn over (ii) On Fig. 21.2, sketch the variation with distance x from the centre of the interference pattern of the intensity observed on the screen up to the fourth order maxima on both sides of the centre. [2] (c) Fig. 21.3 shows the individual waveforms from slit S 1 and slit S 2 at a point P between the zeroth order and the first order maxima of the interference pattern. (i) Using Fig. 21.3, 1. state the phase difference between the waves at point P. phase difference = rad [1] intensity Fig. 21.