Physics Questions and Answers
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
When a red rose flower is observed in blue light, what colour does the observer see?
Red
Blue
Magenta
yellow
No correct option
Correct answer is E
The colour which an object presents to the eye is the colour of light it reflects. Red rose flower will therefore absorb any other colour and reflect red. Therefore when viewed in blue light, it has no colur to reflect and will therefore appear black. Although mixture of red light and blue light = magenta .
When the human eye loses its power of accomodation, the defect is known as
short sightedness
presbyopia
astigmatism
long sightedness
Correct answer is B
presbyopia is loss of accommodation
6 v, 6.0Ω
2 v, 0.7Ω
2 v, 6.0Ω
6 v, 0.7Ω
Correct answer is B
Total energy in parred connection is equal to emt of one cell, = 2v but total internal resistance is given by
(1)/r = (1)/r1 + (1)/r2 + (1)/r3 = (1)/2 + (1)/2 + (1)/2 = (3)/2
∴ r = (2)/3 = 0.67Ω
I, II,III and IV
I, II and III
I, III and IV
I, II and IV
Correct answer is D
No explanation has been provided for this answer.
Steam burn is more severe than that of boiling water because
steam burn is independent of relative humidity
steam possesses greater heat energy per unit mass
water boils at a higher temperature
steam burn is dependent on relative humidity
Correct answer is B
The specific latent heat of vaporization of steam is 2.1 x 106JKg-1
while the energy required to raise the temperature of a unit mass of water from 0°c to 100°c = C x Dt = 4200 x 100 = 420000 = 4.2 x 105 JKg-1
∴ steam possesses greater heat energy per unit mass