12 The graph shows the variation with voltage Vacross a filament lamp with the current I though the lamp mA
30
25
1.5
1.0
# Suggest whether the resistor obeys Ohm's law.
i Calculate the resistance of the lamp when V=4.0 V.
The resistivity of the filament of the lamp at a voltage of 4.0 V is 3.0 x 10-22m. The radius of the
filament is 0.25 mm. Calculate the length of the filament.
05
0.0
00
1.0
2.0
3.0
4.0
5.0
6.0
VIV
[2]
[2]
5 ELECTRICITY AND MAGNETISM
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What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?

People with normal vision cannot focus their eyes underwater if they aren't wearing a face mask or goggles and there is water in contact with their eyes. in a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. with the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 2.05cm in front of the eye.)

Many science fiction movies and tv shows have detected using a nuclear weapon to destroy astroids what problems does plait see with this plan