The mass of water vapour in a given volume of air is 0.05g at 20°C, while the mass of water vapour required to saturate it at the same temperature is 0.15g. Calculate the relative humidity of the air.
- A. 3.33%
- B. 5.55%
- C. 33.33%
- D. 55.55%
A safety precaution designed to prolong the life of a lead acid accumulator is
- A. By topping up the cells with concentrated acid
- B. The use of naked flame when charging the battery
- C. Keeping the specific gravity of the electrolyte within specified range
- D. By connecting wires to the terminals directly when testing the level of charging
A copper rod, 5m long when heated through 10c, expands by 1mm. If a second copper rod, 2.5m long is heated through 5c, by how much will it expand?
- A. 4mm
- B. 0.25mm
- C. 2mm
- D. 0.12mm
Workdone on an object to bring it to a certain point in space is called
- A. Gravitational potential energy
- B. Potential energy
- C. Kinetic energy
- D. Mechanical energy
The length of the seconds hand of laboratory clock is 0.1m. Calculate the speed at the top of the seconds hand
- A. 1.05 × 10\(^{-2}\)ms\(^{-1}\)
- B. 1.85 × 10\(^{-4}\)ms\(^{-1}\)
- C. 9.50 × 10\(^{-1}\)ms\(^{-1}\)
- D. 5.25 × 10\(^{-3}\)ms\(^{-1}\)
A projectile of mass 4kg is fired vertically and reaches a maximum height of 40m. Calculate the potential energy at the highest point
(g = 10ms\(^{-2}\)
- A. 1800J
- B. 1600J
- C. 600J
- D. 440J
The part of the human eye that does similar work as the diaphragm of a camera lens is the
- A. Ciliary muscles
- B. Pupil
- C. Iris
- D. Retina
Heat may be transferred by conduction, convection and radiation. By which of these methods does heat travel through vacuum?
- A. Conduction only
- B. Convection only
- C. Radiation only
- D. All these methods
If the attraction of the sun is suddenly ceased, the earth would continue to move in a straight line making a tangent with the original orbit. This statement is derived from Newton’s
- A. First law of motion
- B. Second law of motion
- C. Third law of motion
- D. Law of universal gravitation
Which of the following characteristics of a wave is used in the measurement of the depth of the Sea?
- A. diffraction
- B. interference
- C. refraction
- D. reflection
Which of these is observed when air is pumped out of a discharge tube without lowering its pressure
- A. the conductivity of the air increases
- B. the conductivity of the air decreases
- C. conduction does not occur
- D. spark are produced
The volume of 0.354g of helium at 273°C and 114cmhg of mercury pressure is 2667cm\(^3\). Calculate the volume
- A. 2000.25 cm\(^3\)
- B. 200.025 cm\(^3\)
- C. 4003.27 cm\(^3\)
- D. 2010.25 cm\(^3\)
When two objects A and B are supplied with the same quantity of heat, the temperature change in A is obtained to be twice that of B. The mass of A is half that of B. The ratio of the specific heat capacity of A to B is
- A. 1 : 4
- B. 4 : 1
- C. 1 : 1
- D. 2 : 1
The following are some units
I. Ns
II. Non
III. Nm\(^{-2}\)
IV. J°K\(^{-1}\)
V. JKg\(^{-1}\)
What are the units of latent heat?
- A. I
- B. II
- C. III
- D. V
A boy pushes a 500kg box along a floor with a force of 2000N. If the velocity of the box is uniform, the co-efficient of friction between the box and the floor is
- A. 1
- B. 0.8
- C. 0.65
- D. 0.4
A coil X is moved quickly away from the end Y of a stationary metal bar and a current then flows in X as shown above.
Then
- A. the bar is not a magnet
- B. Y is a north pole
- C. Y is a South pole
- D. Y repels coil X
If a body moves with a constant speed and at the same time undergoes an acceleration, its motion is said to be
- A. circular
- B. oscillatory
- C. rectilinear
- D. rotational
The lower fixed part of a faulty thermometer reads 2°C while the upper fixed point is 100°C.
What is the true temperature when the thermometer reads 51°C?
- A. 52°C
- B. 50°C
- C. 49°C
- D. 46°C
The resultant capacitance in the figure above is
- A. 0.4μf
- B. 0.8μf
- C. 1.8μf
- D. 4.5μf
The point at which the molecules of a loaded wire begin to slide across each other resulting in a rapid increase in extension is
- A. yield point
- B. proportionality point
- C. deformation point
- D. elastic point
In which of the points labelled A, B, C, D and E on the conductor shown would electric charge tend to concentrate most
- A. A
- B. B
- C. C
- D. E