Two inductors of inductance 4 II and 8 II are arrange in series and a current of 10 A is passed through them. What is the energy stored in them?
- A. 600 J
- B. 50 J
- C. 133 J
- D. 250 J
Under which of the following conditions do gases conduct electricity?
- A. Low presssure and low p.d
- B. low pressure and high p.d
- C. high pressure an low p.d
- D. high pressure and high p.d
If the charge of electricity is K wh is N4, what is the cost of operating an electrical appliance rated 250 v,2 A for six hours?
- A. N28
- B. N12
- C. N16
- D. N24
In measuring high frequency a.c, the instrument used is the
- A. d.c ammeter
- B. moving coil ammeter
- C. moving iron ammeter
- D. hot wire ammeter
Which of the following is a property of steel?
- A. it cannot retain its magnetism longer than iron
- B. it can be used for making temporary magnets
- C. it can be used for making permanent magnets
- D. it can easily be magnetized and demagnetized
The eclipse of the sun occurs when the
- A. moon is between the sun and the earth
- B. earth is between the sun and the moon
- C. moon is not completely hidden in the earth's shadow
- D. moon's umbra falls on some part of the earth
A certain far – sighted person cannot see object that are closer to the eye than 50 cm clearly. Determine the power of the converging lens which will enable him to see at 25 cm
- A. 0.06 D
- B. 0.02 D
- C. 0.03 D
- D. 0.04 D
- E. no option is correct
The capacitance of a parallel plate capacitor is 20 μf in air and 60 μf in the presence of a dielectric. What is the dielectric constant?
- A. 0.3
- B. 6.0
- C. 3.0
- D. 2.0
When a red rose flower is observed in blue light, what colour does the observer see?
- A. Red
- B. Blue
- C. Magenta
- D. yellow
- E. No correct option
When the human eye loses its power of accomodation, the defect is known as
- A. short sightedness
- B. presbyopia
- C. astigmatism
- D. long sightedness
Three similar cells each of e.m.f 2 v and internal resistance 2Ω are connected in parallel, the total e.m.f and total internal resistance are respectively
- A. 6 v, 6.0Ω
- B. 2 v, 0.7Ω
- C. 2 v, 6.0Ω
- D. 6 v, 0.7Ω
I. change of state
II. Diffusion
III. Radiation
IV. Osmosis
which of the processes above can be explained using the kinetic theory?
- A. I, II,III and IV
- B. I, II and III
- C. I, III and IV
- D. I, II and IV
Steam burn is more severe than that of boiling water because
- A. steam burn is independent of relative humidity
- B. steam possesses greater heat energy per unit mass
- C. water boils at a higher temperature
- D. steam burn is dependent on relative humidity
A block of aluminum is heated electrically by a 30 w heater if the temperature rises by 10°c in 5 minutes, the heat capacity of the aluminum is
- A. 900 JK-1
- B. 90 JK-1
- C. 100 JK-1
- D. 200 JK-1
The phenomenon that shows that increase in pressure lowers the melting point can be observed in
- A. sublimation
- B. condensation
- C. coagulation
- D. regelation
A cannon is fired from town X,after how long is the sound heard at a town Y 4.95 km away?
[velocity of sound in the air = 330 ms-1]
- A. 30 s
- B. 10 s
- C. 10 s
- D. 15 s
The ground is always cold at night because the
- A. atmosphere absorbs the sun's energy at night
- B. earth radiates heat to the atmosphere at night
- C. sun no longer shine at night
- D. atmosphere reflects the sun's energy at night
A perfect emitter or absorber of radiant energy is a
- A. conductor
- B. black body
- C. white body
- D. red body
Which of the following electromagnetic waves has the highest frequency?
- A. utra - violet rays
- B. radio waves
- C. x - rays
- D. infrared - rays
Which of the following types of waves needs a medium for propagation?
- A. sound waves
- B. light waves
- C. radio waves
- D. x - rays
Which of the following could be effectively used to reduce friction?
- A. kerosene
- B. grease
- C. water
- D. petrol