JAMB Physics 1990 past questions

What is the reading of the vernier scale above?

Which of the following is a fundamental unit?

Two horizontal forces, 10N and 8N and another force F, inclined at 300 to the vertical acting as shown in the diagram above, keep the body P in equilibrium. The weight of the body is

What is the average velocity of the sprinter whose velocity-time graph is shown in the figure above?

Which of the following statements are correct about an object in equilibrium under parallel forces? I The total clockwise moments of the forces about any point equals the total anticlockwise moments about the same point. II The total forces in one direction equals the total forces in the opposite direction III The resolved components along the x- axis equals the resolved component along the y-axis.

X 2m Y 5N Z [PAGE 39] A force of 5N acts at a point Y on a rod XYZ as shown in the diagram above. If XY is 2m, what is the moment of the force about point X?

To keep a vehicle moving at a constant speed v, requires power P, from the engine. The force provided by the engine is

What is the length of the liquid column in a barometer tube that would support an atmospheric pressure of 102000 Nm-2 if the density of the liquid is 2600 kgm-3? [g = 10 ms-2].

40cm3 of liquid is mixed with 60m3 of another liquid Q. If the density of P and Q are 1.00kg m3 and 1.6kg m3 respectively, what is the density of the mixture?

The resistances of a platinum wire at the ice and steam points are 0.75 ohm and 1.05 ohm respectively. Determine the temperature at which the resistance of the wire is 0.90 ohm

The pressure of a gas when cooled at constant volume will decrease because the molecules

1kg of copper is transferred quickly from boiling water to a block of ice. Calculate the mass of ice melted, neglecting heat loss.

Which of the following conditions will make water boil at a temperature of 1000C when the atmospheric pressure is 750mm Hg?

Which of the following statements are correct? I Land and sea breezes are natural convection currents. II Convection may occur in liquids or gases but not in solids. III The vacuum in thermos flask prevents heat loss due to convection only.

Shadows and eclipse result from the

An object which is 3cm high is placed vertically 10cm in front of a concave mirror. If this object produces an image 40cm from the mirror, the height of the image is

What must be the distance between an object and a converging lens of focal length 20cm to produce an erect image two times the object height?

Which of the following correctly represents the diagram for locating the image P of an object O in a lens if F is the focal point of the lens?

For a short sighted person, light rays from a point on a very distant object is focused

When light is incident on an object which is magenta in colour, which of the following colours be absorbed?

In a resonance tube experiment, the effective length of the air column for the first resonance is 20cm when set into vibration by a tuning fork of frequency 480 Hz. Neglecting end effect, the velocity of sound in air is

An organ pipe closed at one end is 80cm long. Determine the frequency of the fundamental note assuming that the speed of sound in air is 340ms-1.

One of the properties of the earth’s magnetic field is that the

Which of the following statements are true of an insulated charged body carrying a positive charge? I It contains excess positive charges II It creates an electric field III It possesses potential energy IV It carries electric current. [PAGE 41]

Which of the following is a vector?

Three cells each of e.m.f. 1.5V and an internal resistance of 1.0 Ohms are connected in parallel across a load resistance at 2.67 Ohms. Calculate the current in the load?

When a known standard resistor of 2.0 Ohms is connected to the 0.0cm end of a meter bridge the balance point is found to be 55.0cm. what is the value of the unknown resistor?

The total energy required to send a unit positive charge round a complete electrical circuit is the

Which of the following is an essential physical property of the wires used for making fuses?

Which of the following is most suitable for protecting the circuit of a 2000W electric iron connected to a 250V mains?

Electrical power is transmitted at a high voltage rather than low voltage because the amount of energy loss is reduced due to

A 0 – 10 mA galvanometer with a coil resistance of 30 Ohms can be converted to a 0 –10A ammeter by using

What precaution should a manufacturer take to ensure that energy loss in a transformer is minimized?

The photocell works on the principle of the