Aamirah Fathima · Physics Practice Paper — Alternating Current · Electromagnetic Waves · Ray Optics · 120 questions · marked +4 / −1 / 0
360out of 480
75.0%percentage
95correct
20wrong
5blank / void
83%accuracy
Section by section
Section
Chapter
Correct
Wrong
Blank/void
Marks
Accuracy
A
Alternating Current
34
5
1
131/160
87%
B
Electromagnetic Waves
36
3
1
141/160
92%
C
Ray Optics
25
12
3
88/160
68%
Total
95
20
5
360/480
83%
Sub-topic map — where the marks went
Chapter
Sub-topic
Q
✓
✗
—
Marks
Alternating Current
AC fundamentals, rms and peak values
8
5
2
1
18/32
Alternating Current
AC through R, L and C
7
7
0
0
28/28
Alternating Current
Series LCR circuit and impedance
8
7
1
0
27/32
Alternating Current
Power, power factor and wattless current
6
5
1
0
19/24
Alternating Current
Resonance and sharpness
6
6
0
0
24/24
Alternating Current
Transformers and LC oscillations
5
4
1
0
15/20
Electromagnetic Waves
Displacement current and Maxwell's equations
7
6
1
0
23/28
Electromagnetic Waves
Nature and properties of EM waves
8
5
2
1
18/32
Electromagnetic Waves
Speed, E–B relation and energy
9
9
0
0
36/36
Electromagnetic Waves
The electromagnetic spectrum
9
9
0
0
36/36
Electromagnetic Waves
Sources and uses
7
7
0
0
28/28
Ray Optics
Reflection at plane surfaces
7
4
3
0
13/28
Ray Optics
Refraction at plane surfaces
8
6
2
0
22/32
Ray Optics
Apparent depth and real depth
5
2
3
0
5/20
Ray Optics
Total internal reflection
9
4
2
3
14/36
Ray Optics
Refraction through a prism
7
5
2
0
18/28
Ray Optics
Dispersion by a prism
4
4
0
0
16/16
Difficulty profile
Level
Questions
Correct
Wrong
Blank
Accuracy
Easy
45
38
5
2
88%
Moderate
50
38
10
2
79%
Hard
25
19
5
1
79%
What this paper says
Alternating Current and Electromagnetic Waves are exam-ready. Ray Optics is not.
Sections A and B ran at 87% and 92% accuracy and cost 48 marks between them. Section C alone cost 72 — exactly half of
everything she lost on a paper that was one-third Ray Optics. There is no general physics problem here; there is one chapter
that has not been learnt.
Fix in this order
Total internal reflection — 22 of 36 marks gone, and 3 of the 4 blanks on the whole paper sit here.
She did not slow down on this block, she stopped. Rebuild it from two conditions that must both hold: light goes
denser → rarer, and i > C. Then C = sin−1(1/n), and three numbers worth knowing cold:
n = 1.5 → C ≈ 42°, water n = 4/3 → C ≈ 49°, diamond n = 2.42 → C ≈ 24°.
Both her TIR numericals (Q102, Q104) failed on exactly these.
Apparent depth — 15 of 20 marks gone. One relation carries the whole sub-topic:
n = real depth / apparent depth, so apparent depth = t/n and the shift = t(1 − 1/n). The consequence she inverted twice:
a larger n makes the apparent depth smaller, so the coin appears raised by more, not less.
Plane mirrors — 15 of 28 marks gone. Three facts, nothing else: the image is virtual, erect, laterally
inverted and the same size; the minimum mirror height is half the person's height whatever the distance;
and for two mirrors at θ, the number of images is 360/θ − 1.
Prism numericals. Both misses (Q113, Q116) were substitution, not concept:
n = sin((A + δm)/2) / sin(A/2) at minimum deviation, and δ = (n − 1)A for a thin prism.
Write both at the top of the rough sheet before starting any prism block.
Five of the twenty wrongs were tagged Easy — Q82, Q88, Q89, Q101, Q102 are one-line NCERT statements
(definition of refractive index, speed in a medium, what a plane-mirror image is). Those 25 marks come back from reading
the Ray Optics chapter once, properly. They do not need practice.
On the blanks. Four questions left empty, all four in Ray Optics, three of them consecutive
(Q101, Q105, Q106) and ringed in blue. That is the same pattern as Mock 2, where 17 blanks cost 68 marks.
A blank scores 0; a guess between two surviving options is worth +4 or −1, which is a bet she should take every time.
Ringing the number is the right instinct — but come back and fill it.
Two marks need explaining before the error notes. Q1 carries two ticks — one on (A) 440 V and one on (D) 220 V, with the question number ringed in blue.
(D) is right, but on a real OMR sheet a double mark is read as no answer, so it has been scored 0, not −1. In the hall, one answer per question, and erase properly. Q50 was attempted on the first printing of this paper, where the EM-wave diagram was drawn in an oblique projection that made the two curves look offset. That figure was corrected in version 2. The physics she wrote (“π/2 out of phase”) follows the misleading picture, so treat this one as a paper defect, not her error — but do re-read the rule: in vacuum E and B oscillate in phase, mutually perpendicular, both perpendicular to the direction of travel.
SECTION A — ALTERNATING CURRENT — 6 lost
AC fundamentals, rms and peak values
Q1Easydouble-marked 0
The peak value of an alternating voltage is 311 V. Its rms value is nearly