JAMB Physics 1989 Past Questions

Which of the following is a set of vectors?

The magnitude of the resultant of two mutually perpendicular forces, F₁ and F₂ is 13N, if the magnitude of F₁ is 5N, what is the magnitude of F₂?

Two points on a velocity time-graph have coordinates (5s, 10ms^-1) and (20s, 20ms^-1). Calculate the mean acceleration between the two points

A thin film of liquid is trapped between two glass plates. The force required to pull the plates apart will increase if the

A block-and-tackle system is used to lift a load of 20N through a vertical height of 10m. if the efficiency of the system is 40%, how much work is done against friction?

Which of the following devices are used to measure pressure? i. Aneroid barometer. ii. hydrometer. iii. hygrometer. iv. manometer.

A piece of wood of mass 40g and uniform cross-sectional area of 2cm² floats upright in water. The length of the wood immersed is

The pressure on the gas of constant gas thermometer at the ice point is 325mm of mercury and at the steam point is 875mm of mercury. Find the temperature when the pressure of the gas is 190mm of mercury

A column of air 10.0cm long is trapped in a tube at 27^oC. What is the length of the volume at 100^oC?

A mass of gas at 7^oC and 70cm of mercury has a volume of 1200cm³. Determine its volume at 27^oC and pressure of 75cm of mercury.

An electric heater is used to melt a block of ice of mass 1.5kg. If the heater is powered by a 12V battery and a current of 20A flows through the coil, calculate the time taken to melt the block of ice at 0^oC. [specific latent heat of fusion of ice = 336 x 10³Jkg^-1]

From the kinetic theory of gases, temperature is a

A vibrator of frequency 60Hz is used in generating transverse stationary waves in a long thin wire, If the average distance between successive nodes on the wire is 45cm, find the speed of the transverse waves in the wire.

When the tension in a sonometer wire is doubled, the ratio of the new frequency to the initial frequency is

In a sound wave in air, the adjacent rarefactions and compressions are separated by a distance of 17cm. If the velocity of the sound wave is 340ms^-1. Determine the frequency

Light of wavelength 5000 x 10^-8cm travels in free space with a velocity of 3 x 10⁸ms^-1. What is its wavelength in glass of refractive index 1.5?

The magnification of the image of an object placed in front of a convex mirror is \(\frac{1}{3}\). If the radius of curvature of the mirror is 24cm, what is the distance between its object and its image?

The plane mirrors in a kaleidoscope are usually placed

A far sighted person cannot see objects that are less than 100cm away. If this person wants to read a book at 25cm, what type and focal length of lens does he need?

When a yellow card is observed through a blue glass, the card would appear.

Dispersion of light by a glass prism is due to the

Which of the following pairs is NOT part of the electromagnetic spectrum? i. Radio waves. ii. Beta rays. iii. Gamma rays. iv. Alpha rays

Two insulated charged spheres of different sizes and carrying opposite charges are connected together by a metallic conductor. Current will flow from one sphere to the other until both sphere

When a number of identical small magnets are arranged in a line, the strength of the resultant magnet

A bar magnet is most effectively demagnetized by

The resistance of a 5m uniform wire of cross-sectional area 0.2 x 10^-6m² is 0.425. What is the resistivity of the material of the wire?

Three resistors, with substances 250\(\Omega\), 500\(\Omega\) and 1k\(\Omega\) are connected in series. A 6V battery is connected to either end of the combination. Calculate the pot3ential difference between the end of the 250\(\Omega\) resistor.

A calibrated potentiometer is used to measure the e.m.f. of a cell because the

An ammeter of resistance 1.0\(\Omega\) has a full-scale deflection of 50mA. Determine the resultant full-scale deflection of the meter when a shunt of 0.0111\(\Omega\) is connected across its terminals.

The electrochemical equivalent of silver is 0.0012gC^-1. If 36.0g of silver is to be deposited by electrolysis on a surface by passing a steady current for 5.0mins, the current must be

When a radiation strikes a metal surface, electrons may be ejected from the metal. The maximum kinetic energy which may be acquired by an ejected electron depend on the

Which of the following is TRUE of the particles emitted in radioactive disintegration?

Eight alpha decays and six beta decays are necessary before an atom of 2 \(^{238}_{92}U\) achieves stability. The final product in the chain has an atomic number of

An object is placed at 5.6 x 10^-4m in front of a converging lens of focal length 1.0 x 10^-nm. The image formed is

The function of a 5-A fuse included in a circuit supplying a household refrigerator with power is to keep the

The fig above shows a uniform circular object, center R and diameter PS. A circular section 6 and Diameter PR is cut from it. if PQRS is a straight line, where is center of gravity of the figure

A simple pendulum of mass m moves along an arc pf a circle radius R in a vertical plane as shown above. What is the work done by gravity in a downward swing through the angle q to 0 degree

A block of mass m is held in equilibrium against a vertical wall by a horizontal force. If the coefficient of friction between the wall and the block is µ, the minimum value of the horizontal force is

In the fig above W1 = 200g, and W2 =450g . Calculate the extension of the spring per unit load?

[g = 10ms^-2]

The air column as shown above is set into vibration by the turning fork. In this State of resonance, the waves in the air column will be

In the above circuit diagrams A is the ammeter and V is the Voltmeter. Which of the circuits is correct for finding the correct value of the resistance R

Three 2-µF capacitors are arranged as seen in the circuit above . The effective capacitance between E and F is

The total power drawn from the cell in the circuit above is

The fig above shows a conductor PQ carrying a current I in the direction shown. At a particular position near the conductor is a compass needle K. Neglecting the earth's magnetic field, the compass needle will

A beam of radiation is passed between a pair of charged plates as indicated in the fig above. Beam P is undetected While Q is deflected to the left. P and Q respectively should be

I.γ-rays β-rays
II. x-rays β-rays
III. γ-rays x-rays
IV. x-rays x-rays