JAMB Physics 2000 Past Questions

When a ship sails from salt water into fresh water, the fraction of its volume above the water surface will

I. Its velocity is constant
II. No work is done on the body
III. It has constant acceleration directed away from the centre
IV. The centripetal force is directed towards the centre

Which combination of the above is true of a body moving with constant speed in a circular track?

The velocity ratio of a machine is 5 and its efficiency is 75%. What effort would be needed to lift a load of 150N with the machine?

At a fixed point below a liquid surface, the pressure downwards is P₁ and pressure upwards is P₂. It can be deduced that

If the force and the velocity on a system are each reduced simultaneously by half, the power of the system is

A catapult used to hold a stone of mass 500g is extended by 20cm with an applied force F. If the stone leaves with a velocity of 40m/s, the value of F is

A stream is flowing at 0.75ms^-1 and a boat heading perpendicular for the stream landed at the opposite bank at an angle of 30°. Calculate the velocity of the boat.

A rope is being used to pull a mass of 10kg vertically upward. Determine the tension in the rope if, starting from rest, the mass acquires a velocity of 4ms^-1 in 8s [g = 10ms^-2]

I. The frictional force is independent of the area of the surfaces in conduct
II. The frictional force depends on the nature of the surfaces in contact
III. The frictional force depends on the speed of sliding
IV. The frictional force is directly proportional to the normal reaction.

Which combination of the above is true of sliding friction?

Total internal reflection occurs when light moves from

A quantity of water at 0°C is heated to about 30°C. At each degree rise in temperature, its density will

I. Coherence
II. Same frequency
III. Same wavelength
IV. Same Intensity

Which of the conditions above are necessary to produce interference fringes?

A boy observes a piece of stone at the bottom of a river 6.0m deep. If he looks from the surface of the river, what is the apparent distance of the stone from him? [Refractive Index of Water = 4/3]

A thin wire with heavy weights attached to both ends is hung over a block of ice resting on two supports. If the wire cuts through the ice block while the block remains solid behind the wire, the process is called

Dry
Day 1 - 30°C | Day 2 - 29°C | Day 3 - 25°C

Wet
Day 1 - 22°C | Day 2 - 22°C | Day 3 - 21°C

The reading above are for three consecutive days from a wet and dry bulb hygrometer. It can be concluded that the relative humidity for the three days

One end of a long wire is fixed while a vibrator is attached to the other end. When the vibrator is energized, the types of waves generated in the wire are

A metal of mass 0.5kg is heated to 100°C and then transferred to a well-lagged calorimeter of heat capacity 80JK^-1 containing water of heat capacity 420JK^-1 at 15°C. If the final steady temperature of the mixture is 25°C, find the specific heat capacity of the metal.

The main reason for making the cover of a vacuum flask airtight is to prevent heat loss by

A radio is operated by eight cells each of e.m.f. 2.0V connected in series. If two of the cells are wrongly connected, the net e.m.f. of the radio is

If a charged ion goes through combined electric and magnetic fields, the resultant emergent velocity of the ion is

A projection lantern is used to give the image of a slide on a screen. If the image is 24 times as large as the slide and the screen is 72.0m from the projecting lens, what is the position of the slide from the lens?

An electron of charge 1.6 x 10^-19C and mass 9.1 x 10^-31kg is accelerated between two metal plates with a velocity of 4 x 10⁷ms^-1, the potential difference between the plates is

A cell of internal resistance 0.01Ω can be measured accurately using the

What optical instrument can best be constructed with converging lenses of focal lengths 50cm and 5cm?

in a pure semiconductor, the number of electrons in the conduction band is

In a thermonuclear reaction, the total initial mass is 5.02 x 10^-27kg and the total final mass is 0.01 x 10^-27kg. The energy released in the process is
[c = 3.0 x 10⁸ms^-1]

A gas would serve as an electrical conductor under

An electric generator with a power output of 3.0KW at a voltage of 1.5KV distributes power along cables of resistance 20.0Ω. The power loss in the cables is

If the frequency of an emitted x-ray is 1.6 x 10¹⁶Hz, the accelerating potential is?
[e = 1.6 x 10^-19C, h = 6.63 x 10^-34Js]

If the fraction of the atoms of a radioactive material left after 120years is 1/64, what is the half-life of the material?

A certain radioactive source emits radiations that were found to be deflected by both magnetic and electric fields. The radiations are

A 2H inductor has negligible resistance and is connected to a 50/π Hz A.C. Supply. The reactance of the inductor is

A cell of internal resistance 1Ω supplies current to an external resistor of 3Ω. The efficiency of the cell is

A conductor of length 2m carries a current of 0.8A while kept in a magnetic field of magnetic flux density 0.5T. The maximum force acting on it is

Light of energy 5eV falls on a metal of work function 3eV and electrons are liberated. The stopping potential is

The velocity y of a particle in a time t is given by the equation
y = 10 + 2t²
Find the instantaneous acceleration after 5 seconds

A simple pendulum has a period of 17.0s. When the length is shorten by 1.5m, its period is 8.5s. Calculate the original length of the pendulum

A sonometer wire is vibrating at frequency f_o. If the tension in the wire is doubted while the length and the mass per unit length are kept constant, the new frequency of vibration is

A travelling wave moving from left to right has an amplitude of 0.15m, a frequency of 550Hz and a wavelength of 0.01m. The equation describing the wave is

A transverse wave is applied to a string whose mass per unit length is 3 x 10^-2kgm^-1. If the string is under a tension 12N, the speed of the propagation of the wave is

An engineer intends to deviate a light ray from its path by 120^o through reflection from a plane mirror. Calculate the angle of incidence

The diagram above shows a maximum and minimum thermometer divided into three portions P, Q and R. Which of the following is true about the respective content of P,Q and R

The diagram above shows two capacitors P and Q of capacitance 5μF and 10μF. Find the charges stored in P and Q respectively

In the diagram above a beam of white light travels from a rare to a dense medium. What colours of light do the rays a, b and c respectively represents?

In the diagram above, the values of V₁ and V₂ are respectively

The correct position for a fuse in the diagram above is

If current flows in the direction of the arrows in the solenoid above, the north pole is at

In the a.c circuit above, the current value is

A handbag containing some load weighing 162N is carried by two students each holding the handle of the bag next to him. If each handle is pulled \( 60^{\circ} \) to the vertical, find the force on each student's arm