11-Waves-1-Mark-Scheme.pdf - 11 Waves 1 Exam-style mark...

11 Waves 1
Exam-style mark scheme OCR Physics A
Question Answer Marks Guidance
1 a The radiant power passing through a surface per unit
area. B1
1 b i A and B should be one wavelength apart
B1 Peak to peak, trough to
trough, or any correct answer
1 b ii The number of waves passing a set point in 1 second
hertz/Hz
B1
B1
1 b iii
Wave 1:
Wavelength = 0.8 m
Amplitude = 10 cm
Wave 2:
Wavelength = 1.4 m
Amplitude = 5 cm
B1
B1
B1
B1
No alternative answers
allowed
1 c i Longitudinal:
Oscillation parallel to direction of energy transfer
Transverse:
Oscillation at 90° (or perpendicular) to direction of
energy transfer
(Sound waves are) longitudinal
B1
B1
B1
1 c ii
T = 5 squares
s 1 . 0 10 20 5
3
= × × =
−
T
1 . 0
1 1
= =
T
f
10 Hz
M1
M1
A1 Unit required for mark.
2 a i (At least) one normal drawn
Refraction at both glass–air boundaries
Correct angle of reflection
B1
B1
B1
Must be at point where a ray
meets a boundary.
Needed when ray enters and
leaves the glass.