Q1.The dispersion of light would result in which of the following phenomena?
A.Eclipse
B.Shadow
Rainbow
D.Mirage
Explanation: Dispersion of light occurs when white light separates into its component colors due to different wavelengths refracting at different angles, forming a rainbow.
Q2.The best color of shirt to be worn on a bright noon day is
A.Red
B.Black
C.Green
White
Explanation: White color reflects most sunlight, keeping the wearer cooler compared to darker colors that absorb more heat.
Q3.The image formed when an object is placed between the focus and centre of a converging lens is
Real, inverted and magnified
B.Real, inverted and diminished
C.Erect, virtual and magnified
D.Erect, virtual and diminished
Explanation: For a converging lens, an object between F and 2F produces a real, inverted, and magnified image beyond 2F.
Q4.For a charged body moving in an electric and magnetic crossed field, the ratio of the electric field intensity, E to the magnetic flux density, B is known as
A.Lorentz ratio
B.Charge ratio
Velocity selector
D.Electrochemical equivalence
Explanation: The ratio E/B gives the velocity at which the electric force balances the magnetic force, selecting particles of that speed in a velocity selector.
Q5.A note, K from a keyboard has an amplitude of 0.5cm and frequency 2000Hz. Another note, M from a guitar has an amplitude of 1.5cm and frequency 2000Hz. Which of the following statements is true if the two notes are compared?
A.K is louder than M
M is louder than K
C.M has a higher pitch than K
D.K and M have the same timbre
Explanation: Loudness depends on amplitude; higher amplitude (1.5cm for M) means M is louder. Same frequency means same pitch, and timbre differs due to different instruments.
Q6.A simple pendulum of length 0.8m is set oscillating on a planet. If the pendulum completes 20 oscillations in 60s, calculate the acceleration due to gravity on this planet. [π = 3.14]
A.2.5ms⁻²
3.0ms⁻²
C.3.5ms⁻²
D.3.8ms⁻²
Explanation: Time period T = 60s / 20 = 3s. T = 2π√(L/g), so g = 4π²L / T² = 4*(3.14)²*0.8 / 9 ≈ 3.0 ms⁻².
Q7.A liquid of mass 2kg at 61°C is kept in a lagged vessel. If another 2kg of the same liquid at 21°C is added to the liquid in the vessel, calculate the final temperature of the mixture
A.50°C
41°C
C.30°C
D.15°C
Explanation: Assuming no heat loss, heat lost = heat gained: 2m c (61 - θ) = 2m c (θ - 21), so θ = (61 + 21)/2 = 41°C.
Q8.If two bodies, A and B are each in thermal equilibrium with another body C, then the three bodies are in thermal equilibrium with each other. This is the statement of
Zeroth law of thermodynamics
B.First law of thermodynamics
C.Second law of thermodynamics
D.Third law of thermodynamics
Explanation: The zeroth law defines temperature and thermal equilibrium transitively, allowing thermometers to work.
Q9.What is the S.I unit of electric charge?
A.Ampere
Coulomb
C.Volt
D.Ohm
Explanation: The S.I unit of electric charge is the coulomb (C), defined as the charge transported by 1 ampere in 1 second.
Q10.A body of mass 5kg falls freely from rest. Calculate the kinetic energy after 2 seconds [g = 10ms⁻²]
A.50J
100J
C.150J
D.200J
Explanation: Velocity after 2s, v = gt = 10*2 = 20 ms⁻¹. KE = (1/2)mv² = 0.5*5*400 = 100 J.
Q11.The speed of light in medium A of refractive index 1.5 is 2.0 × 10⁸ms⁻¹. Determine the speed of light in medium B of refractive index 1.2
A.1.8 × 10⁸ms⁻¹
2.5 × 10⁸ms⁻¹
C.2.7 × 10⁸ms⁻¹
D.3.0 × 10⁸ms⁻¹
Explanation: Speed in vacuum c = n_A * v_A = 1.5 * 2.0e8 = 3.0e8 ms⁻¹. Then v_B = c / n_B = 3.0e8 / 1.2 = 2.5e8 ms⁻¹.
Q12.The wavelength of a sound note travelling with a speed of 360ms⁻¹ is 600m. Determine the period of the note
A.60,000s
B.6,000s
1.667s
D.0.167s
Explanation: Period T = λ / v = 600 / 360 ≈ 1.667 s.
Q13.In which of the following levers is the effort applied between the load and the fulcrum?
A.Pliers
B.Wheelbarrow
Sugar tongs
D.Table knife
Explanation: Sugar tongs are a class 3 lever where the effort is applied between the fulcrum and the load.
Q14.A current of 2A flows through a resistor of 5Ω. Calculate the power dissipated in the resistor
A.10W
20W
C.30W
D.40W
Explanation: Power P = I²R = 2² * 5 = 20 W.
Q15.Calculate the potential difference across a 10Ω resistor when a current of 0.5A flows through it
A.2V
5V
C.10V
D.15V
Explanation: V = IR = 0.5 * 10 = 5 V.
Q16.Which of the statements is correct about the nucleus of an atom? I. is centrally located in the atom. II. contains the nucleons and electrons. III. is positively charged due to the protons. IV. decays when there is instability inside.
A.I, II and IV only
I, III, and IV only
C.I, II and III only
D.I and II only
Explanation: The nucleus is central (I), positively charged due to protons (III), and decays if unstable (IV). It contains nucleons (protons and neutrons), not electrons (II wrong).
Q17.A radioactive element of mass 16g was isolated and stored. It was discovered that after 40 days only 1g of the element remained undecayed. Calculate the half-life of the element
A.2.5days
B.5.0days
10.0days
D.15.0days
Explanation: From 16g to 1g is 4 half-lives (16→8→4→2→1). Time = 40 days, so half-life = 40/4 = 10 days.
Q18.Which of the following reasons explains why the walls and ceilings of a standard concert hall are usually covered with perforated pads? To
A.increase the intensity of sound waves
B.increase the loudness of sound waves
reduce the effect of reverberation of sound waves
D.decrease the frequency of sound waves
Explanation: Perforated pads absorb sound waves, reducing echoes and reverberation for clearer acoustics.
Q19.A bucket of water of mass 10kg is swung in a vertical circle of radius 1.2m. While at the lowest position of the swing, its speed is 5ms⁻¹. Determine the tension in the string (g = 10ms⁻²)
A.41.7N
B.141.7N
C.208.3N
308.3N
Explanation: At lowest point, T - mg = mv²/r, T = mg + mv²/r = 10*10 + 10*25/1.2 = 100 + 208.3 ≈ 308.3 N.
Q20.A man's near point is 30cm. Which of the following eye defects is the man likely to suffer from?
Hypermetropia
B.Myopia
C.Presbyopia
D.Astigmatism
Explanation: Hypermetropia (farsightedness) has a near point farther than normal (25 cm), so 30 cm indicates hypermetropia.
Q21.White light can be produced by a combination of I. magenta, yellow and cyan. II. red, blue and green. III. magenta and green. IV. yellow, red and green.
II only
B.I, II and III only
C.I and IV
D.II and III only
Explanation: White light is produced by additive primary colors: red, green, and blue (II). The others do not combine to white.
Q22.What is the S.I unit of power?
Watt
B.Joule
C.Newton
D.Pascal
Explanation: The S.I unit of power is the watt (W), which is joule per second.
Q23.Which of the following statements about stationary wave is not true?
A.Particles between adjacent nodes vibrate out of phase with each other
B.Successive nodes or antinodes occur at intervals of half a wavelength
Particles between adjacent nodes vibrate in phase with each other
D.Particles between adjacent nodes have different amplitudes
Explanation: In a stationary wave, particles between adjacent nodes are out of phase (180°), not in phase.
Q24.In a pipe closed at one end and open at the other end, the overtones that accompany the fundamental frequency are
odd integer multiples of the fundamental frequency
B.even integer multiples of the fundamental frequency
C.all integer multiples of the fundamental frequency
D.prime integer multiples of the fundamental frequency
Explanation: A closed pipe produces only odd harmonics (overtones) due to the boundary conditions.
Q25.A radioactive substance of mass 512.0g decays to 64.0g. Determine the number of half-life involved in the decay
A.8
B.6
C.4
3
Explanation: 512 / 64 = 8, and 2³ = 8, so 3 half-lives.
Q26.Two waves will interfere destructively if the path difference between the waves is
A.one wavelength
one-half wavelength
C.two wavelengths
D.zero
Explanation: Destructive interference occurs when path difference is an odd multiple of λ/2, such as λ/2.
Q27.A radioactive substance of mass 16g at GMT: 13:00 hour was received at a hospital. The half-life of the substance is 2 hours. Determine the fraction of the substance left after 4 hours
A.½
¼
C.1/8
D.1/16
Explanation: After 4 hours = 2 half-lives, fraction left = (1/2)² = 1/4.
Q28.The mechanical advantage of a hospital bed is 1.71. Which of the following statements is correct? The effort applied
is less than the weight of the bed
B.is greater than the weight of the bed
C.equals the weight of the bed
D.cannot be determined
Explanation: MA = load/effort = 1.71 > 1, so effort < load (weight).
Q29.A sound from a microphone is transformed to electrical energy. The type of energy stored is
A.nuclear chemical energy
electrical energy
C.sound energy
D.thermal energy
Explanation: The microphone converts sound energy into electrical energy, which is then stored or transmitted.
Q30.Calculate the velocity ratio of an inclined plane inclined at 45° to the horizontal
Q31.The angle between the velocity vector and the acceleration vector for a body in uniform circular motion is
A.45°
B.60°
90°
D.120°
Explanation: In uniform circular motion, acceleration is centripetal, perpendicular to velocity, so 90°.
Q32.The S.I unit of the power consumed by a system is
A.Newton
B.Coulomb
Watt
D.Tesla
Explanation: Power is measured in watts (W), the S.I unit for rate of energy transfer.
Q33.The secondary coil of a transformer has more turns than the primary coil. If the number of turns in the secondary coil is 500 and the primary coil is 250, the step-up transformer is
2:1
B.1:2
C.1:4
D.4:1
Explanation: Turns ratio N_s : N_p = 500 : 250 = 2:1, step-up since N_s > N_p.
Q34.Which of the following statements is correct about the nucleus of an atom? It
A.contains electrons
B.is negatively charged
is positively charged
D.decays when there is stability
Explanation: The nucleus contains protons (positive charge) and neutrons, making it positively charged.
Q35.A radium nuclide decays by emitting alpha particle as shown below: ²²⁶₈₈Ra → X + ⁴₂He. Determine the daughter nuclide
Q37.An electron moving with a speed of 5.0 × 10⁵ms⁻¹ enters a uniform magnetic field at 90°. Calculate the magnitude of the magnetic force on the electron if the magnetic field intensity is 0.25T [e = 1.6 × 10⁻¹⁹C]
A.1.5 × 10⁻¹⁴N
2.0 × 10⁻¹⁴N
C.2.5 × 10⁻¹⁴N
D.3.5 × 10⁻¹⁴N
Explanation: F = q v B sin90° = 1.6e-19 * 5.0e5 * 0.25 = 2.0 × 10⁻¹⁴ N.
Q38.A beam of light which appears to come from a point in space is said to be
A.convergent
divergent
C.parallel
D.circular
Explanation: A divergent beam appears to originate from a virtual point source behind the observer.
Q39.A sound wave made up of large number of unrelated frequencies superimposed on each other is called
A.harmonies
B.note
noise
D.pitch
Explanation: Noise consists of a random superposition of many unrelated frequencies, unlike musical notes with harmonics.
Q40.A boy pushes a box of mass 80kg along a horizontal floor with a force of 200N. If the box is pushed with a uniform velocity, what is the coefficient of friction between the box and the floor? [g = 10ms⁻²]
0.25
B.0.40
C.0.50
D.0.65
Explanation: For uniform velocity, F = frictional force = μ mg, so μ = F / (mg) = 200 / (80 * 10) = 0.25.