2012 JAMB Physics Past Questions

In order to remove the error of parallax when taking measurements with a metre rule, the eye should be focused

A load is pulled at a uniform speed along a horizontal floor by a rope at 45° to the floor. If the force in the rope is 1500 N, what is the frictional force on the load?

From the velocity-time graph shown above, which of the following quantities CANNOT be determined?

Calculate the total distance covered by a train before coming to rest if its initial speed is 30 ms^-1 with a constant retardation of 0.1 m/s^-2.

A car starts from rest and moves with a uniform acceleration of 30 ms^-2 for 20 s. Calculate the distance covered at the end of the motion.

A rocket is fired from the earth’s surface to a distant planet. By Newton’s law of universal gravitation, the force F will

If a freely suspended object is pulled to one side and released, it oscillates about the point of suspension because the _____?

An object moves in a circular path of radius 0.5 m with a speed of 1 ms^-1.What is its angular velocity?

The diagram above shows a wooden block just about to slide down an inclined plane whose inclination to the horizontal is oc. The coefficient of frictional force between the block and the plane is

An object of mass 20 kg slides down an inclined plane at an angle of 30° to the horizontal. The coefficient of static friction is

[g = 10 ms^-2]

A block and tackle is used to raise a load of 250 N through a vertical distance of 30 m. What is the efficiency of the system if the work done against friction is 1500 J?

If a load of 1 kg stretches a cord by 1.2 cm, what is the force constant of the cord?
[g = 10 ms^-2]

From the diagram above, calculate the work done when the particle moves from x = 0 m to x = 80 m

An object of volume 1 m³ and mass 2 kg is totally immersed in a liquid of density 1 kgm^-3 . Calculate its apparent weight.

The pressure at any point in a liquid at rest depends only on the

A balloon whose volume is 300 m³ is filled with hydrogen. If the density of air is 1.3 kgm^-3, find the upthrust on the balloon.

[g = 10ms^-2]

Clinical thermometers are examples of _________.

Two metals P and Q are heated through the same temperature difference. If the ratio of the linear expansivities of P to Q is 2: 3 and the ratio of their length is 3 : 4 respectively, the ratio of the increase in lengths of P to Q is

2000 cm³ of a gas is collected at 27°C and 700 mmHg. What is the volume of the gas at standard temperature and pressure?

Calculate the temperature change when 500 J of heat is supplied to 100 g of water.

[Heat capacity of water = 4200 J/(kg K)]

Which of the following is not a factor that can increase the rate of evaporation of water in a lake?

The quantity of heat energy required to melt completely 1 kg of ice at – 30°C is _______.

• latent heat of fusion = 3.5 × 10 ⁵ Jkg ^-1
• specific heat capacity of ice = 2.1 × 10 ³ Jkg ^-1K ^-1

I. It is a rapid, constant and irregular motion of tiny particles.
II. It gives evidence that tiny particles of matter called molecules exist.
III. It takes place only in gases.
IV. It gives evidence that molecules are in a constant state of random motion.

Which of the combinations above is correct about Brownian motion?

The equation of a wave traveling in a horizontal direction is expressed as:

y = \( \scriptsize 15 \: sin \normalsize \frac{2 \pi}{5} \scriptsize (60t\:-\:x) \)

What is its wavelength?

From the diagram above, if the particle F is at a distance X from O to the right, the phase of the vibration will be different from that at O by

Which of the following factors will affect the velocity of sound?

The characteristic of a vibration that determines its intensity is the _____.

Where can a man place his face to get an enlarged image when using a concave mirror to shave?

A pinhole camera is placed 300 m in front of a building so that the image is formed on a screen 5 cm from the pinhole. If the image is 2.5 cm high, the height of the building will be

The magnification of an object 2 cm tall when placed 10 cm in front of a plane mirror is ______.

After reflection from the concave mirror, rays of light from the sun converges ___?

A glass block of thickness 10 cm is placed on an object. If an observer views the object vertically, the displacement of the object is _____.

[The refractive index of glass ng is 1.5]

I. Rays of light travel from a less dense medium to a denser medium.
II. The Angle of incidence is greater than critical angle.
III. Rays of light travel from a denser medium to a less dense medium.

Which of the statements above are conditions for total internal reflection to occur?

The use of lenses is not applicable in the

Dispersion of white light is the ability of white light to

A newly charged 12 V accumulator can easily start a car whereas eight new dry cells in series with an effective e.m.f. of 12 V cannot start the same car because

Six identical cells, each of e.m.f 2 V are connected as shown above. The effective e.m.f. of the cell is

The fuse in an electric device is always connected to the _____.

A particle carrying a charge of 1. 0 × 10^-8 C enters a magnetic field at 3.0 × 10^-2 ms ^-1 at right angles to the field. If the force on this particle is 1.8 × 10^-8 N, what is the magnitude of the field?

Which of the following is the correct shape of the graph of capacitive reactance X versus frequency F for a pure capacitor in an a.c. circuit?

A conductor of length 1 m moves with a velocity of 50 ms^-1 at an angle of 30° to the direction of a uniform magnetic field of flux density 1.5 Wbm^-2. What is the e.m.f. induced in the conductor?

The current output form of an ac. source is given as I = 10 sin ωt. The d.c equivalent of the current is

The process of detecting a pin mistakenly swallowed by a child is x – ray

Which of the following particles cannot be deflected by both electric and magnetic fields?

A piece of radioactive material contains 1000 atoms. If its half-life is 20 seconds, the time taken for 125 atoms to remain is

The p-n junction diodes can act as rectifiers because they

If a reverse-biased voltage is applied across a p-n junction, the depletion layer width is ____?

I.       Small size
II.     Low power requirement
III.    Not easily damaged by high temperature
IV.     Highly durable

Which of the above are the advantages of semiconductors?