OCR 2023 GCE Physics B H157/02: Physics in depth AS Level Question Paper & Mark Scheme (Merged)

2 © OCR 2023 Section A 1 A ball is thrown with an initial speed of 14 ms –1 at an angle of 56° to the horizontal, as shown in the diagram. The ball leaves the thrower’s hand at a vertical distance of 1.7m above the ground. (a) Write down the horizontal and vertical components of velocity of the ball at the instant it is thrown. horizontal component, uH =....................................................... ms –1 vertical component, uV = ...................................................... ms –1 [2] (b) Calculate the maximum height above the ground reached by the ball. You can assume that air resistance is negligible. height = ...................................................... m [2] (c) Calculate the horizontal distance between the point where the ball is thrown and the point where it reaches its maximum height. distance =....................................................... m [2] 56° 3 © OCR 2023 Turn over 2 A light-emitting diode (LED) emits monochromatic blue light of wavelength 470nm. Each photon emitted is produced by a single electron crossing the LED. (a) Calculate the work done by an electron in the LED as one photon of blue light is emitted. work done = ....................................................... J [2] (b) Explain why a p.d. of 2.60V across the LED would not result in the emission of light. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ........................................................................................................................................... [2] (c) In use, the LED draws an electric current of 30mA. Calculate the number of photons emitted each second, assuming that the energy efficiency of a blue LED is 93%. number per second = ........