5 Turn over 7 The intensity of light incident on a light dependent resistor (LDR) can vary both its electrical resistance R and the number of charge carriers per unit volume n. The light intensity on an LDR is increased. Which row of the table describes the effect on R and n? R n A decreases decreases B decreases increases C increases decreases D increases increases (Total for Question 7 = 1 mark) 8 A proton has a mass of 1.67 × 10 −27 kg. Which of the following shows the conversion of this mass to GeV/c2 ? A 1 67 10 1 60 10 3 00 10 27 10 8 2 . . ( . ) × × × × − − B 1 67 10 1 60 10 3 00 10 27 19 8 2 . . ( . ) × × × × − − C 1 67 10 3 00 10 1 60 10 27 8 2 10 . ( . ) . D 1 67 10 1 60 10 3 00 10 27 10 8 2 . . ( . ) (Total for Question 8 = 1 mark) 9 The blade of a lawnmower rotates at a speed of 50 revolutions per second. Which of the following is the angular speed of the blade in rads s−1? A 7.96 B 15.9 C 157 D 314 (Total for Question 9 = 1 mark)