NABTEB Physics Questions Objective and Theory Update
Are you wondering where you can find NABTEB Physics Questions that can guide you before participating in the NABTEB exams?
NABTEB, established by the Federal Government in 1992, aims to make exams less complicated, especially those involving hands-on skills like technical and trade-related tasks.
They organize exams like the National Technical Examination (NTC), National Business Certificate (NBC), and their advanced levels (ANBC and ANTC).
We have compiled lots of NABTEB physics questions and answers to help you in your preparations.
NABTEB Physics Questions and Answers (Objective)
There are lots of objective and theory questions with answers provided below which have been repeated over the years of NABTEB physics exams.
These questions and answers will help prepare you for the forthcoming exams.
Question 1
What is the SI unit of electric charge?
a) Ampere (A)
b) Coulomb (C)
c) Volt (V)
d) Ohm (Ω)
Answer: b) Coulomb (C)
Question 2
According to Newton’s third law of motion, for every action, there is an equal and opposite:
a) Force
b) Acceleration
c) Reaction
d) Momentum
Answer: c) Reaction
Question 3
Which of the following is a fundamental particle with a negative charge?
a) Proton
b) Neutron
c) Electron
d) Photon
Answer: c) Electron
Question 4
What does the acronym “LASER” stand for?
a) Light Amplification by Stimulated Emission of Radiation
b) Long-range Atomic Spectrum Emission and Reflection
c) Laser Amplification through Specialized Energetic Resonance
d) Light Absorption by Selective Electron Reflection
Answer: a) Light Amplification by Stimulated Emission of Radiation
Question 5
In the electromagnetic spectrum, which type of radiation has the highest frequency?
a) Radio waves
b) Microwaves
c) X-rays
d) Gamma rays
Answer: d) Gamma rays
Question 6
What is the law of conservation of energy?
a) Energy cannot be created
b) Energy cannot be destroyed
c) Energy can be transformed from one form to another
d) All of the above
Answer: d) All of the above
Question 7
Which planet is known as the “Red Planet”?
a) Venus
b) Mars
c) Jupiter
d) Saturn
Answer: b) Mars
Question 8
What is the formula for calculating the force exerted by a spring?
a) F = ma
b) F = kx
c) F = pV
d) F = G(m1m2/r^2)
Answer: b) F = kx
Question 9
What is the unit of measurement for frequency?
a) Hertz (Hz)
b) Watts (W)
c) Joules (J)
d) Tesla (T)
Answer: a) Hertz (Hz)
Question 10
According to the theory of relativity, as an object’s speed approaches the speed of light, its:
a) Mass decreases
b) Mass increases
c) Mass remains constant
d) Volume decreases
Answer: b) Mass increases
Question 11
Which law states that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of individual gases?
a) Boyle’s law
b) Charles’s law
c) Dalton’s law
d) Gay-Lussac’s law
Answer: c) Dalton’s law
Question 12
What is the unit of power?
a) Watt (W)
b) Joule (J)
c) Newton (N)
d) Volt (V)
Answer: a) Watt (W)
Question 13
What is the phenomenon where a wave bends as it passes from one medium to another?
a) Reflection
b) Diffraction
c) Refraction
d) Interference
Answer: c) Refraction
Question 14
Which particle is responsible for carrying the electromagnetic force?
a) Photon
b) Gluon
c) W boson
d) Z boson
Answer: a) Photon
Question 15
What is the primary function of an optical lens?
a) To magnify objects
b) To produce colors
c) To focus or diverge light
d) To block light
Answer: c) To focus or diverge light
Question 16
According to Archimedes’ principle, an object submerged in a fluid experiences a buoyant force equal to the:
a) Weight of the fluid displaced
b) Volume of the fluid displaced
c) Density of the fluid displaced
d) Acceleration of the fluid displaced
Answer: a) Weight of the fluid displaced
Question 17
What is the unit of electrical resistance?
a) Ampere (A)
b) Ohm (Ω)
c) Volt (V)
d) Watt (W)
Answer: b) Ohm (Ω)
Question 18
Which law states that the total energy of an isolated system remains constant over time?
a) Law of Conservation of Mass
b) Law of Conservation of Energy
c) Law of Conservation of Momentum
d) Law of Universal Gravitation
Answer: b) Law of Conservation of Energy
Question 19
What is the SI unit of magnetic flux?
a) Tesla (T)
b) Weber (Wb)
c) Gauss (G)
d) Ampere (A)
Answer: b) Weber (Wb)
Question 20
What is the speed of light in a vacuum?
a) 300,000 km/s
b) 150,000 km/s
c) 500,000 km/s
d) 1,000,000 km/s
Answer: a) 300,000 km/s
NABTEB Physics Theory Questions and Answers
Question 1a
State Hook’s law
Answer: Hooks law states that provided the elastic limit of an elastic material is not exceeded, the
extension of the materials is directly proportional to the load or force applied. (F = K X).
F = KX (Provided the elastic limit is not exceeded)
Where F = Applied force or load, X = Extension, K = Proportionality constant or force constant
Question 1b
If a spring has a stiffness of 1000 Nm–1. What work will be done by extending the spring by 100 mm?
Answer: Work done = ½ FX = ½ KX2
K = stiffness constant = 100Nm-1
X = Extension of spring = 100mm = 0.1m
Work done = ½ x 1000 x (.1)2 Joules
= ½ x 1000 .01J
W = 5.0J
Question 2a
Distinguish between electric conductors and insulators. Give FOUR examples of each.
Answer: Electric conductors are materials that will allow easy movement of electrons through them.
Insulators are materials that do not allow easy movement of electrons through them. A good conductor of electricity is a good conductor of heat.
Examples of conductors are metal, damp air, salt solution, graphite, carbon black, the Earth, and the human body. (Any 4 examples)
Examples of insulators: polythene, bakelite ebonite, dry paper, dry hair, silk, oil, glass, wood, and sulfur (Any 4 examples)
Question 2b
What is a capacitor? Name three types of capacitors and THREE appliances that use capacitors for operation.
Answer: A capacitor is a device for storing electric charges or for storing electricity
The three types of capacitors are (1) Variable air capacitor, (2) paper capacitor, (3) Electrolytic capacitor
Appliances that use capacitors are:
1. Radio tune circuit
2. Car ignition system
3. Induction coil to eliminate spark when a circuit containing inductance is opened suddenly.
4. Fluorescent light tube starter
5. Starter of electric pumping machine (Any 3 as an example)
Question 3(a)
State Newton’s first and second laws of motion
Answer: Newton’s law states that A body will continue in its state of rest or uniform motion along a straight line unless it is acted upon by an (external) impressed force.
Newton’s 2nd Law states that the time rate of change of momentum of a body (mass x velocity) is proportional to the resultant force acting on it (and it takes place) along the direction of action of this force.
Question 3(b)
Explain the difference between force and impulse
Answer: Force is that push or pull that will change or tend to change the state of rest or uniform motion of a body.
While impulse is the product of the (average) force acting on a body and the time duration during which it acts.
OR Force – mass x acceleration while impulse = Force x time of action
OR Unit of force = Newton Unit of impulse = NS
Question 4(a)(i)
Explain using kinetic/molecular theory of matter why solid aluminum will change to
liquid at 6600C without a change in its temperature.
Answer: Molecules of solid are in a fixed position in the crystalline structure. They are held together
by intermolecular forces. This constraint makes them vibrate about their mean equilibrium position. Aluminum is a solid.
As the temperature of the solid Aluminium increases the atoms acquire greater kinetic energy.
And can vibrate farther apart from their mean position, thus weakening the intermolecular forces binding them together.
At a certain maximum temperature (6600C)the molecules have maximum kinetic energy(K.E).
This maximum temperature is the melting point of the solid. Further heat supplied to the substance does not increase the kinetic energy of molecules.
Instead, the heat energy is used to break down the intermolecular forces binding the molecules together in the solid.
The molecules are then free and could slide over one another. The solid then melts at this maximum temperature.
Further heating only goes to break more bonds while the temperature remains constant.
The heat energy absorbed during this process is known as the latent heat of fusion.
Question 4a(ii)
Explain why evaporation causes cooling and give the factors that affect its rate.
Answer: The molecules of the liquid have an average velocity or average kinetic energy which increases with temperature.
Molecules near the surface which happen to move faster the average, escape from the attraction of their neighours and out of the liquid.
Thus the liquid loses its most energetic molecules while the less energetic ones are left behind.
The average K.E. of the remaining molecules is therefore reduced, which lowers the temperature of the liquid hence evaporation causes cooling.
Factors that affect evaporation are:
1. Temperature
2. Exposed area of liquid surface
3. Prevailing wind
4. Humidity
5. Prevailing atmospheric pressure
Question 4b(i)
Describe an experiment to measure the specific heat capacity of a solid.
Answer: The specific heat capacity of a solid in the form of a metal block can be determined by an
electrical method and method of mixture.
(1). By Electrical Method
Two holes are bored in the block, after which the block is weighed. A thermometer and an electrical heater are inserted in each of the holes.
A little oil in each hole keeps establishing good thermal contact with the block.
The initial temperature of the block is noted the electrical heater is switched on and the current is allowed to flow for some time until the temperature rises by about 150C.
The exact time of flow of a known current is measured with a stop-watch and the initial final temperatures of the metal block are measured by the thermometer.
Heat supplied by current, H=ivt jules.
The heat required to raise the temperature of the block by 00C = MC
IVt = MC
C = IVt kg-1k
(2) By Method of Mixture
The solid is in the form of a brass or copper block is sighted, tied to a string, and left for some minutes in a beaker of boiling water.
The calorimeter together with the stirrer is first weighed empty and re-weighted when it is about two-thirds full of water.
The initial temperature of the water is read with the thermometer.
After the solid has stayed in the boiling water for about 15 minutes it is quickly transferred into the water in the calorimeter.
The calorimeter is covered with the lid, and the water is gently stirred to ensure a uniform distribution of temperature.
The highest steady temperature of the mixture is read and recorded.
Question 5(a)(i)
Distinguish between intrinsic and extrinsic semiconductors and give TWO examples of each.
Answer: If conduction in a material results only from the electron movement from valence to the conduction band, it is called an intrinsic semiconductor.
While semiconductor materials containing different types of impurities are combined to produce the many useful devices presently on the scene.
The process of adding impurity to a semiconductor is called doping, and the doped semiconductor is referred to as extrinsic semi-conduction.
E.g. (i) Intrinsic – Pure silicon, Germinium, etc.
(ii) Extrinsic: – Gallium Arsenide, (gasa), Lead Tellurium (PbTe) etc.
Question 5a(ii)
What is a p-n Junction and how dos it work?
Answer: P-n junction consists of a p-type and n-type semiconductor in contact.
When forward bias (i.e. the P-semiconductor is connected to the positive terminal of a battery and the n-semiconductor is connected to the negative terminal of a battery).
It has a low resistance to current flow.
When in reverse bias (i.e. the P-semiconductor is connected to the negative terminal of the battery and then the Semiconductor is connected to the positive terminal).
It has a high resistance to current flow.
Question 5b(iii)
Mention Two sources of energy loss in a transformer and how they can be reduced.
Answer: Two forms of energy loss in a transformer are: (Any two)
1. eddy current
2. heat loss (12R)/Joules heat or copper loses.
3. Magnetic flux leakage.
4. Hysteresis
This energy loss can be reduced by;
1. Eddy current can be reduced by laminating the core
2. Heat loss can be reduced by using thick wires, or low-resistance wire to form the coils
3. Magnetic flux leakage – by efficient core design.
4. Hysteresis – by soft iron core or special alloy
These are not real NABTEB Physics Questions, but likely repeated questions over the years to help candidates understand the nature of their examinations.
Ensure to note every question provided on this page, understanding how things work and applying that knowledge to real-life situations.
