2014 JAMB PHYSICS PAST QUESTIONS AND ANSWERS

The question specifies the type as “Type F” based on the provided options.

A meter rule’s least count is typically $0.1$ mm, reflecting its smallest measurable division.

Displacement requires both magnitude and direction, distinguishing it from scalar quantities like distance or mass.

Torque and momentum are vectors, as they both have magnitude and direction based on cross or linear product.

Wheels of a moving car undergo translational motion across the road and rotational motion about their axis.

Zero acceleration corresponds to flat sections on a velocity-time graph, indicating constant velocity.

Use equation $v^2 = u^2 + 2as$ to $v = 12$ ms$^{-1}$, where $u = 0$, $a = 3$, and $s = 24$.

Escape velocity $v_e = \sqrt{\frac{2GM}{R}}$ to $v_e = 11.3$ km/s.

Weight $W = mg$ to $W = 80 \times \frac{10}{3} = 36$ N.

An object is in equilibrium when the vector sum of all acting forces equals zero.

In equilibrium, the lines of action of the three forces meet at a single point or are concurrent.

K.E. at ground = P.E. lost = $mgh = 20 \times 10 \times 10 = 2000$ J.

Nuclear energy is converted into heat, which can be used to generate electrical energy via turbines.

Effort = $\frac{\text{Load}}{\text{Efficiency} \times \text{Velocity Ratio}} = \frac{1000}{0.75 \times 4} = 333.33$ N.

Efficiency = $\frac{\text{Load} \times \text{Axle Radius}}{\text{Effort} \times \text{Wheel Radius}} \times 100$

Stress = $\frac{\text{Force}}{\text{Area}} = \frac{500}{0.2} = 2.5 \times 10^3$ N/m$^2$.

Elastic limit is the maximum stress before permanent deformation occurs, marked as point Q on the diagram.

Dew forms due to condensation of water vapor on cool surfaces like grass during early morning.

Celsius temperature = Kelvin temperature – 273 = 20 – 273 = -253°C.

Volume change = $V_0 \beta \Delta T$ to $20000 \times 9 \times 10^{-6} \times 30 = 5.4$ cm$^3$. Final volume = 20005.4 cm$^3$.

Charles’ Law holds when volume is directly proportional to temperature at constant pressure, i.e., $a=0$, $b=1$, $c=-1$.

Heat capacity is the amount of heat required to raise the temperature of the body by 1 K or 1 °C.

The melting point of a substance is the temperature at which it changes from solid to liquid, i.e., liquidification temperature.

The dew point is the temperature at which air becomes fully saturated with water vapor, leading to condensation.

Convection occurs due to variations in liquid density, causing less dense, hotter regions to rise and denser, cooler regions to sink.

Frequency = $\frac{\text{Velocity}}{\text{Wavelength}} = \frac{300}{0.15} = 2000$ Hz.

Distance to hill = $\frac{\text{Velocity} \times \text{Time}}{2} = \frac{330 \times 0.8}{2} = 132$ m.

In a closed tube, length of resonating column is $\frac{\text{Wavelength}}{4} = \frac{40}{4} = 10$ cm.

Magnification = $\frac{\text{Image distance}}{\text{Object distance}} = \frac{25}{1000} = 0.025$.

$\frac{1}{f} = \frac{1}{u} + \frac{1}{v}$, solve for $v$: $\frac{1}{2} = \frac{1}{8} + \frac{1}{v}$ to $v = 2.67$ cm.

Both the objective and eyepiece lenses in a compound microscope are short focal length lenses to provide high magnification.

When a telescope is in normal use, the final image is formed at infinity for comfortable viewing without eye strain.

When the negative rod approaches, electrons are repelled towards the leaf, reducing its divergence momentarily.

Charge $Q = C \times V = 0.1 \times 10 = 1$ C.

The total capacitance is calculated based on parallel and series combinations. Result: 2 μF.

Maximum power transfer occurs when the external resistance matches the internal resistance of the cell.

$\rho = \frac{R \cdot A}{L} = \frac{60 \cdot 0.8 \times 10^{-6}}{4} = 1.2 \times 10^{-6}$ Ωm.

A 300 Ω resistor in parallel with the circuit reduces the resistance effectively to 120 Ω.

PHCN measures electrical energy in kilowatt-hours (kWh), where 1 kWh = 1000 Wh.

The solenoid method gradually reduces the magnetic field by applying an alternating current through a solenoid.

At the equator, the magnetic field is horizontal, so the angle of dip is 0°.

The diagram represents a step-up transformer, which increases voltage and decreases current.

The electromotive force in the secondary winding varies depending on the transformer design and load.

This is a nuclear fusion reaction where two lighter nuclei combine to form a heavier nucleus and release energy.

During beta decay, a neutron is converted into a proton, so the atomic number increases by one.

$m = zIt$, $z = 3.3 \times 10^{-7}$ kgC$^{-1}$, $I = 4$ A, $t = 7200$ s. $m = 3.3 \times 10^{-7} \times 4 \times 7200 = 9.5 \times 10^{-3}$ kg.

Neon produces a pink glow in a discharge tube when an electric current passes through it.

The decay emits two alpha particles and two beta particles.

In a common emitter configuration, the output voltage is provided through the collector terminal.

The bond between silicon and germanium is covalent because they share electrons in their outer shells.