1020 ' (L7) (ii) 3 accept '

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1 Level 7 Physics Questions - Answers 1. (a) (i) Paul James Sylvia accept light accept vibration accept sound answers must be in the correct order all three answers in the correct order are required for the mark (ii) 3 accept ' 1020 ' 340 (b) (i) the energy or the sound is more spread out accept some of the sound is absorbed by the air accept the amplitude decreases vibrations decrease is insufficient (ii) 2 (L7) award one mark for a wave with a smaller amplitude award one mark for a wave with the same frequency award the marks for a wave with the correct amplitude and frequency but which is not centred on the middle line of the grid or which is not in phase with the drawn wave the marks may be awarded for a wave drawn on Sylvia s grid 2. (a) (i) 2 accept Ncm accept cmn accept 0.02 Nm for both marks (ii) 2 (Ncm) accept 0.02 Nm accept the same unit not required the mark for the unit may be awarded here if not given in part (a)(i) accept the numerical answer to (a)(i) Moulsham High School 1

2 (iii) 0.1 accept the numerical answer to (a)(ii) 20 accept the numerical answer to (a)(i) 20 if (a)(ii) has been omitted or if the answer given to (a)(ii) is the same (b) 0.3 accept the answer to (a)(iii) (a) (i) add more coils or turns 1 (L6) accept put coils or turns closer together do not accept move it closer increase the current 1 (L6) accept increase the number of cells or batteries accept increase the voltage or power (ii) all four poles must be correct for the mark (b) (i) any one from steel stays magnetised iron loses its magnetism the switch would stay closed the switch would not spring open (ii) copper is a better conductor than iron accept the converse accept copper has a lower resistance accept iron or the reed switch has a greater resistance 4. (a) X-axis: time (minutes) Y-axis: temperature ( C) appropriate scales such as 2 cm represents 10 C, 2 cm represents 1 minute 11 points plotted to within half a small square a smooth curve of best fit (not dot-to-dot) pupils can gain credit for correct responses to other parts if the axes are wrongly labelled both answers are required for the mark units are required for the mark at least one zero must be included at the origin Moulsham High School 2

3 (b) an answer consistent with the drawn curve 1 (L6) accept a tolerance of one small square 5. (a) (i) 75 accept Nm do not accept lower case n (ii) 750 accept or accept the numerical answer to part (i) 0.1 (b) any one from a current flows in the coil the coil or the iron core accept there is a magnetic field or the becomes magnetised electromagnet switches on do not accept the core becomes magnetic any one from the counterweight is attracted to the coil or core or the electromagnet the electromagnet produces a bigger moment accept the left-hand side of the barrier moves down the right-hand side moves up is insufficient (a) (i) 12.5 m/s accept m/s 32 accept metres per second or ms 1 for m/s the unit is required for the mark do not accept mps (ii) they are equal or the same accept they are balanced (b) the forward force is greater than accept the converse the backward force accept the forward force is greater or the backward force is smaller do not accept the forward force becomes greater or increases any one from because air resistance or drag is smaller or reduced because there is a smaller surface area accept less friction she is more streamlined is insufficient as it is given in the question [4] Moulsham High School 3

4 7. (a) (i) any one from the Earth rotates accept the Sun appears to move across the sky accept the Sun is in a different position at different times of day the amount of sunlight varies accept different cloud cover the angle of the Sun varies accept in the middle of the day the energy received is greatest do not accept in the middle of the day the Sun is hottest or brightest (ii) 6.0 accept any number from 5.8 to (L6) (b) (i) a graph starting after 6 am and ending before 6 pm a line below the existing line and flat or reaching a maximum between 12 noon and 1 pm 180 (ii) 15 accept (a) (i) constant speed or steady speed accept not accelerating (ii) stationary or not moving accept steady speed of zero or stopped do not accept it has a steady speed (b) accept 10 m/s accept metres per second or ms 1 do not accept mps (c) (i) The forward force was zero and friction was greater than zero. if more than one box is ticked, award no mark (ii) 6 accept answers from 5.8 to 6.2 [6] 9. (a) 0.96 accept Ncm accept cmn accept for both marks Nm do not accept lower case n for N the mark for the unit may be given in (b) ( i) provided it is not contradicted in part ( a) (b) (i) any one from Ncm the same as the carbon dioxide balloon accept the same numerical answer given in (a) ( the unit is not required) accept the same Moulsham High School 4

5 (ii) 0.02 accept numerical answer to (b) (i) 48 [4] 10. (a) any one from white light is a mixture of colours white light contains green light the green light passes through 1 accept for two marks all the other colours are absorbed or filtered out accept for two marks only the green light passes through (b) (i) red because red light passes through the filter both the colour and explanation are required for the mark (ii) black accept she cannot see it any one from 1 because red light will not pass through a green filter absorbs red light accept only green light passes through Moulsham High School 5