If the leaves a positively charged electroscope collapse completely as an object is brought near the cap of the electroscope, the objects possesses
- A. an equal amount of positive charge
- B. less amount of negative charge
- C. no charge
- D. a positive charge
- E. an equal amount of negative charge
A sounding tuning fork is brought near the end of a pipe containing an air column and the loudness of the sound increases. This effect is due to
- A. diffraction
- B. an echo
- C. resonance
- D. interference
- E. reverberation
A boy standing a distance from the foot of a tall cliff claps his hands and hears an echo 0.5s later. If the speed of sound is 340ms1, how far is he from the cliff?
- A. 17m
- B. 34m
- C. 85m
- D. 170m
- E. 680m
Which of the following statement s is/are not correct about a standing wave? I. It is formed by the superimposition of two progressive waves traveling in the same direction II. All points on the wave are vibrating with maximum displacement III. It is formed by the superimposition of two progressive waves of different amplitudes traveling in opposite directions
- A. I only
- B. II only
- C. I and II only
- D. II and III only
- E. I,II and III
A source of sounds produces waves in air of wavelength1.65m. If the speed of sound in air is 330ms-1 the period of vibration in seconds is
- A. 200
- B. 2.0
- C. 0.5
- D. 0.02
- E. 0.005
The change of the direction of a wave-front because of a change in the velocity of the wave in another medium is called?
- A. refraction
- B. reflection
- C. diffraction
- D. interference
- E. dispersion
The ability of the eye to focus objects at different distances is called
- A. power
- B. accommodation
- C. normal vision
- D. persistence of vision
- E. long sight
An object is placed 36cm from a converging lens of focal length 24cm.If a real image which is 4cm high is formed, Calculate the height of the object.
- A. 2.0cm
- B. 4.0cm
- C. 6.0cm
- D. 8.0cm
- E. 10.0cm
The velocities of light in air and glass are 3.0 x10\(^8\)ms\(^{-1}\) and 1.8 \(\times \)10\(^8\) ms\(^{-1}\) respectively. Calculate the sine of the angle of incidence that will produce an angle of refraction of 30° for a ray of light incident on glass.
- A. 1.2
- B. 1.0
- C. 0.8
- D. 0.6
- E. 0.3
A transparent rectangular block 5.0cm thick is placed on a black dot. The dot when viewed from above is seem 3.0cm from the top of the block calculate the refractive index of the material of the block.
- A. 2/5
- B. 3/5
- C. 3/2
- D. 5/3
- E. 5/2
Which of the following statements is/are not correct about image formed by a plane mirror?
I. The magnification produced is 1
II. The image distance is same as the object distance
III. The image is real
IV. The image is laterally inverted
- A. I only
- B. II only
- C. III only
- D. I & II only
- E. II & IV only
Which of the following will affect the saturation vapour pressure of a liquid?
- A. Temperature of the liquid
- B. Humidity of air
- C. Volume of vapour
- D. Volume of the liquid
- E. mass of the liquid
Which of the following instrument may be used to measure the relative humidity?
- A. Hydrometer
- B. Barometer
- C. Manometer
- D. Hypsometer
- E. Hygrometer
The temperature at which the water vapour present in the air is just sufficient to saturate it is called the
- A. ice point
- B. boiling point
- C. steam point
- D. dew point
- E. saturation point
0.5kg of water at 10oC is completely converted to ice by extracting 188000J of heat from it. If the specific heat capacity of water is 4200J kg-1C-1, calculate the specific latent heat of fusion of ice.
- A. 9.0 KJ kg-1
- B. 84.0 KJ kg-1
- C. 168.0 KJ kg-1
- D. 334.0 KJ kg-1
- E. 336.0 KJ kg-1
Which of the following statements about radiant heat is/are not correct?
I. radiant heat cannot travel through a vacuum
II. rough surfaces emit radiant heat more than polished surfaces
III. Dark surfaces absorb radiant heat more than bright surfaces
- A. I only
- B. II only
- C. III only
- D. I & II only
- E. II & III only
Which of the following best explains a person suffers more severe burns when his skin is exposed to steam than when boiling water is poured onto his skin?
- A. steam is at a higher temperature than boiling water
- B. steam posses greater heat energy per unit-mass than boiling water
- C. steam spreads more easily over a wider area of the skin than boiling water
- D. steam panetrates more easily over a wider area of the skin than boiling water
- E. the specific latent heat of vaporization is released in changing from boiling water to steam
In which of the following is the expansion of solids a disadvantage?
- A. the fitting of wheels in rims
- B. fire alarms
- C. the thermostat
- D. the bimatellic thermometer
- E. the balance wheel of a watch
Which of the following is a reason why a concrete floor feels colder to the bare feet than a mat on the same floor during the rainy season?
- A. A mat if s better conductor of heat than the feet
- B. Mat losses heat to the bare feet at a faster rate than concrete floor
- C. Mat losses heat to the bare feet while the concrete floor extracts heat from them
- D. Concrete floor is a better conductor of heat than the mat
- E. Mat is a better conductor of heat than the floor
A given mass of gas has a pressure of 80Nm-2 at a temperature of 47oC. If the temperature is reduced to 27oC with the volume remaining constant, the new pressure is
- A. 46.0 Nm-2
- B. 75.0 Nm-2
- C. 80.0 Nm-2
- D. 85.3 Nm-2
- E. 139.4 Nm-2
The clinical thermometer is characterized by having a
- A. wide range of temperature
- B. wide bore
- C. long stem
- D. constriction
- E. narrow bore