Section A (50 marks) Answer Both Questions Compulsory Questions Q.1. Thickness of Time taken for the Rate of temperature insulation (x)/cm temperature to fall 5.0 C/s fall (AT/At)/ Cs-1 In((AT/At)/"Cs-1) 2.0 110 0.0455 -3.09 3.1 127 0.0393 -3.24 43 149 0.0336 -3.39 5.1 165 0.0303 -3.50 6.4 195 0.0256 -3.67 7.2 216 0.0231 -3.77 a) Plot a graph of In ((47/ )/'Cs-1) (vertical axis) against (x)/cm (horizontal axis). (15 marks) b) Determine the slope of the graph indicating the units. (10 marks) Total 25 Marks CAVENDISH UNIVERSITY Q.2. UGANDA The voltage input to an electrical device and the current through it were measured. The graph below was drawn from the results. 1.5 1.0 0.5 0.1 0.2 0 3 0.4 0.5 V Determine the y-intercept on the graph. Total 25 Marks Cavendish University Uganda - Examination, December, 2022 Page 2 of 4Section B (50 marks) Answer two Questions Q.3. (a) A piece of dust carries a charge of -4.8 x 10-18C, and lies at rest between two parallel plates separated by a distance of 1.5cm. Calculate the force on the charge when a potential difference of 4500 V is applied across the plates. (b) An electric shower is designed to work from a 230V mains supply. It heats water as it passes through narrow tubes prior to the water passing through the shower head. Water enters the heater at 12 'C and when the flow rate is 0.12kgs-' it leaves at 28*C. Calculate the current in the heater, assuming that energy losses are negligible. (specific heat capacity of water - 4200]kg-1 *C-1) Total 25 Marks Q.4. CAVENDISH A "O nucleus absorbs a neutron. The newly formed nucleus subsequently decays to form a 'F nucleus. (a) Write an equation to show the change when the neutron is absorbed. ( b ) Deduce what type of particle is emitted when the decay of the newly formed nucleus occurs. +12 V 1642 8.02 Out o Calculate the output potential in the circuit. Total 25 Marks Cavendish University Uganda - Examination, December, 2022 Page 3 of 4