I & IV only
II & IV only
III & IV only
I, II and III only
Correct answer is D
- Waves are produced by vibration
- Waves transmit energy along the medium
- Particles of a medium vibrate with the wave motion without the entire medium
- Some waves require medium for transmission (mechanical).
The angular dispersion of a prism depends on
The index of refraction only
The angle of incidence as well as the index of refraction
The angle of incidence only
The thickness of the prism only
Correct answer is A
Dispersion is due to different refractive indices speeds and wavelengths.
3.33%
5.55%
33.33%
55.55%
Correct answer is C
| RH | = | mass of water vapour in volume of air
mass of water vapour for saturation |
| RH | = | m
M |
= | 0.05
0.15 |
× | 100 | = | 5
0.15 |
= | 500
15 |
= | 33.33% |
A safety precaution designed to prolong the life of a lead acid accumulator is
By topping up the cells with concentrated acid
The use of naked flame when charging the battery
Keeping the specific gravity of the electrolyte within specified range
By connecting wires to the terminals directly when testing the level of charging
Correct answer is C
- Topping is done with distilled water
- Naked flame should be avoided when charging the battery
- Direct connection of wires to the terminals should be avoided.
4mm
0.25mm
2mm
0.12mm
Correct answer is B
l\(_1\) = 5m, ΔT = 10c, l\(_2\) - l\(_1\) = 1mm
l\(_1\) = 2.5m, ΔT = 5c, l\(_2\) - l\(_1\) = ?
| using | α | = | l\(_2\) - l\(_1\)
l\(_1\)ΔT |
| 1
5(10) |
= | l\(_2\) - l\(_1\)
2.5(5) |
| l\(_2\) | - | l\(_2\) | = | 2.5(5)
5(10) |
= | 1
4 |
= | 0.25mm |