1. C [1] 2. D [1] 3. D [1] 4. A [1] 5. (a) (i) the amplitude is constant; 1

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1 1. C. D 3. D 4. A 5. (a) (i) the amplitude is constant 1 period is 0.0s a max = π = = m s x T Award [] for correct bald answer and ignore any negative signs in answer. (iii) displacement at t = 0.1 cm is ( )1.6 cm π v = x = 0.37 m s 1 0 x = 31.4 (.0 10 ) ( ) T Accept displacement in range 1.60 to 1.70 cm for an answer in range 0.33 m s 1 to 0.38 m s 1. or π v 0 = x 0 = 0.68 m s 1 T π v = v = = = 0.37 m s 1 0 sin t v 0.68 sin[ ] T or drawing a tangent at 0.1 s measurement of slope of tangent Accept answer in range 0.33 m s 1 to 0.38 m s 1. (iv) to the right 1 IB Questionbank Physics 1

2 1 (b) (i) use of f = T 1 and so f = = 5.0 Hz 0. 0 wavelength is 16 cm and so speed is v(= f λ = ) = 0.80 m s 1 (c) (i) points at 0, 8 and 16 cm stay in the same place points at 4 and 0 cm move cm to the right point at 1 cm moves cm to the left 3 the point at 8 cm 1 [14] 6. C 7. A 8. C 9. C 10. (a) the maximum displacement of the system from equilibrium/ from centre of motion / OWTTE 1 IB Questionbank Physics

3 (b) (i) the amplitude of the oscillations/(total) energy decreases (with time) because a force always opposes direction of motion/there is a resistive force/there is a friction force Do not allow bald friction. g ω = l 0.3 T = π 9.81 = 0.80 s 3 (c) (i) upwards 1 y 0 = 0.050(m) and y = 0.030(m) π ω = = 7.85 (rad s 1 ) 0.80 v = 7.85 [ 0.05] [0.03] = 0.31 m s 1 (allow working in cm to give 31cm s 1 ) 4 (iii) λ = 4.0 m 1 recognition that f = (= 1.5) 0.80 (f λ =)v = (= 5.0 m s 1 ) 3 (iv) y = 3.0 cm, d = 0.6m 1 [15] 11. D the point at 8 cm 1 [14] IB Questionbank Physics 3

4 1. (a) the maximum displacement of the system from equilibrium/ from centre of motion / OWTTE 1 (b) (i) the amplitude of the oscillations/(total) energy decreases (with time) because a force always opposes direction of motion/there is a resistive force/there is a friction force Do not allow bald friction. the displacement and acceleration/force acting on (the surface) are in opposite directions g (iii) ω = l 0.3 T = π 9.81 = 0.80 s 3 (c) (i) upwards 1 y 0 = 0.050(m) and y = 0.030(m) π ω = = 7.85 (rad s 1 ) 0.80 v = 7.85 [ 0.05] [0.03] = 0.31 m s 1 (allow working in cm to give 31cm s 1 ) 4 (iii) λ = 4.0 m 1 recognition that f = (= 1.5) 0.80 (f λ =)v = (= 5.0 m s 1 ) 3 (iv) y = 3.0 cm, d = 0.6m 1 (d) (i) wave reflects at ends (of string) interference/superposition occurs (between waves) regions of maximum displacement/zero displacement form (that do not move)(*) one region of max displacement/antinode forms at centre with zero displacement/node at each end(*) (* allow these marking points from a clear diagram ) 3 max IB Questionbank Physics 4

5 the waves (in a string) are transverse and vibrate only in one plane light waves are transverse electromagnetic waves (and) for polarized light the electric field vector vibrates only in one plane 3 (e) Brewster angle = tan 1 [1.3] = 5 θ = (90 5 =) 38 [5] 13. C 14. C 15. A 16. (a) (i) 1.0 mm mm 1 (iii) 37 Hz 1 (iv) 0. m s 1 1 (b) (i) ray: direction in which energy travels wavefront: line connecting points with same phase/displacement sin 60 sin r = 1.4 r = 38 IB Questionbank Physics 5

6 (iii) wavefronts continuous at boundary and parallel wavefronts closer together and equally spaced by eye and in the correct direction (c) (i) reference to superposition/interference waves (almost) cancel to give zero/small displacement where waves arrive out of phase/180 out/π out 3 position of any one minimum closer to centre / minima closer together frequency increased so wavelength decreased / correct explanation in terms of double-slit equation [15] 17. (a) (a wave) that transfers energy between points (in a medium) 1 (b) (i) 1.0 mm mm 1 (iii) 37 Hz 1 (iv) 0. m s 1 1 IB Questionbank Physics 6

7 (c) (i) wavefronts continuous at boundary and parallel wavefronts closer together and equally spaced by eye and in the correct direction ca = 1.4 c b = d d a b d d a b =.0 3 (d) (i) reference to superposition/interference waves (almost) cancel to give zero/small displacement where waves arrive out of phase/180 out/π out 3 position of any one minimum closer to centre / minima closer together frequency increased so wavelength decreased / correct explanation in terms of double-slit equation [15] 18. D 19. B IB Questionbank Physics 7

8 0. C 1. (a) (i) upwards 1 the acceleration is proportional to the displacement from equilibrium and is directed towards equilibrium / opposite to displacement (iii) ω 14 = l ω 4π = : T l = 40 = 0.70m 3 (b) sine curve / negative sine curve 1 (c) (i) ω 14 = = 0 rad max acceleration = (0 0.1 =).4 m s any point where v = 0 1 (d) (i) period = 1.4 s λ 0.45 c = = = 0.3 m s 1 T (iii) 0.57 or [15] IB Questionbank Physics 8

9 . A 3. D IB Questionbank Physics 9