A blacksmith heated a metal whose cubic expansivity is 6.3 x 10\(^{-6}\)K\(^{-1}\). The area expansivity is
- A. 2.0 x 10-6K-1
- B. 2.1 x 10-6K-1
- C. 4.2 x 10-6K-1
- D. 6.3 x 10-6K-1
A boy drags a bag of rice along a smooth horizontal floor with a force of 2N applied at the angle of 60o to the floor. The work done after a distance of 3m is
- A. 3 J
- B. 4 J
- C. 5 J
- D. 6 J
In the diagram above, a rod 50 cm long of uniform cross-section is suspended horizontally on a fulcrum, F, by the action of two forces. What is the weight of the rod?
- A. 40N
- B. 80N
- C. 120N
- D. 200N
From the diagram above, the bob of the pendulum has the fastest speed at
- A. X
- B. Y
- C. Z
- D. W
The figure above shows 4 forces 3N, 10N, 3โ3N and 6N acting on a particle P. The resultant of he four forces is
- A. 5N
- B. 5โ 3N
- C. 10N
- D. 10โ 3N
Silicon doped with aluminum and germanium doped with arsenic become?
- A. p- and n- types respectively
- B. n- en p- type respectively
- C. p- type semiconductor
- D. n- type semiconductors
The bond that forms a semiconductor is?
- A. covalent
- B. electrovalent
- C. ionic
- D. metallic
The energy E of a photon and it’s wavelength are related by Eฮป = X. the numerical value of X is?
[h = 6.63 x 10-34js, c = 3 x 108 ms-1]
- A. 6.6 X 10-28
- B. 1.99 X 10-27
- C. 6.60 x 10-26
- D. 1.99 x 10-25
A charge 50 ยตc has electric field strength of 360 NC-1 at a certain point. The electric field strength due to another charge 120 ยตc kept at the same distance apart and in the same medium is?
- A. 864 NC-1
- B. 150 NC-1
- C. 144 NC-1
- D. 18 NC-1
The production of pure spectrum could easily be achieved using a?
- A. glass prism with a pin
- B. triangular prism with two convex lens
- C. traingular prism only
- D. triangular prism with two concave lenses
When an object is placed between the principal focus and the optical center of a convex lens, it could be used as a?
- A. Simple microscope
- B. refecting lens
- C. compound microscope
- D. projector
A glass plate 0.9cm thick has a reflective index of 1.50. how long does it take for a pulse of light to pass through the plate?
[c = 3.0 x 10\(^8\) ms-1]
- A. 4.5 x 10-11s
- B. 4.5 x 10-10s
- C. 4 .5 x 10-12 s
- D. 3.0 x 10-10s
The instrument used by designers to obtain different color pattern is called?
- A. periscope
- B. sextant
- C. episcope
- D. kaleidoscope
The phenomenon of light bending round an obstacle is?
- A. diffraction
- B. refraction
- C. reflection
- D. polarization
In a large telecommunications auditorium, perforated absorbent materials are used to line the ceiling so as to
- A. Increase the reverberation of sound in the hall
- B. increase the amount of echo in the hall
- C. reduce the hight of the ceiling from the floor
- D. reduce the reverberation of sound in the hall
I. They should be identical
II. They should originate from the same source.
III. They should be coherent.
IV. They should be monochromatic.
from the statements above, the conditions for two waves to interfere are?
- A. I,II and III only
- B. I, III and IV only
- C. II, III and IV only
- D. I, II, III and IV
The blade of a hoe feel colder to touch in the morning than the wooden handle because the
- A. handle is a better conductor of heat than blade
- B. handle contains stored energy in form of heat
- C. blade is a better conductor of heat than the handle
- D. blade is placed at a lower temperature than the heat
I. Mass
II. Density
III. Temperature
IV. Nature of substance
which of the above affect diffusion?
- A. I and II only
- B. I,II and IV only
- C. II, III and IV only
- D. I, II, III and IV
I. Increase the melting point of the liquid.
II. Increase the boiling point of the liquid.
III. Decrease the melting point of the liquid.
IV. Decrease the boiling point of the liquid.
which of the statement above about the effect on increase in pressure in a liquid are correct?
- A. I and II only
- B. I and III only
- C. II and III only
- D. III and IV only
2 kg of water is heated with a heating coil which draws 3.5 A from a 200 V mains for 2 minutes. what is the increase in temperature of the water?
[specific heat capacity of water = 4200 jkg -1k-1]
- A. 30ยฐ
- B. 25ยฐ
- C. 15ยฐ
- D. 10ยฐ
I. Use a liquid with a high melting point.
II. use a liquid of high volume expansivity.
III. use a capillary tube of large diameter.
which of the above best describes how the sensitivity of a liquid-in-glass thermometer can be enhanced?
- A. I only
- B. II. only
- C. I and II only
- D. II and III only