2014 JAMB PHYSICS PAST QUESTIONS AND ANSWERS

$$\text{The question specifies the type as “Type F” based on the provided options.}$$

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

$$\text{Displacement requires both magnitude and direction, distinguishing it from scalar quantities like distance or mass.}$$

$$\text{Torque and momentum are vectors, as they both have magnitude and direction based on cross or linear product.}$$

$$\text{Wheels of a moving car undergo translational motion across the road and rotational motion about their axis.}$$

$$\text{Zero acceleration corresponds to flat sections on a velocity-time graph, indicating constant velocity.}$$

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

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

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

$$\text{An object is in equilibrium when the vector sum of all acting forces equals zero.}$$

$$\text{In equilibrium, the lines of action of the three forces meet at a single point or are concurrent.}$$

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

$$\text{Nuclear energy is converted into heat, which can be used to generate electrical energy via turbines.}$$

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

`\text{Efficiency } = \frac{\text{Load} \times \text{Axle Radius}}{\text{Effort} \times \text{Wheel Radius}} = \frac{800 \times 200}{250 \times 800} \times 100.}

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

$$\text{Elastic limit is the maximum stress before permanent deformation occurs, marked as point } Q \text{ on the diagram.}$$

$$\text{Dew forms due to condensation of water vapor on cool surfaces like grass during early morning.}$$

$$\text{Celsius temperature } = \text{Kelvin temperature } – 273 = 20 – 273 = -253^{\circ}\text{ C.}$$

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

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

$$\text{Heat capacity is the amount of heat required to raise the temperature of the body by 1 K or 1 °C.}$$

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

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

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

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

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

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

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

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

$$\text{Both the objective and eyepiece lenses in a compound microscope are short focal length lenses to provide high magnification.}$$

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

$$\text{When the negative rod approaches, electrons are repelled towards the leaf, reducing its divergence momentarily.}$$

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

$$\text{The total capacitance is calculated based on parallel and series combinations. Result: } 2 \text{ μF.}$$

$$\text{Maximum power transfer occurs when the external resistance matches the internal resistance of the cell.}$$

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

$$\text{A } 300 \Omega \text{ resistor in parallel with the circuit reduces the resistance effectively to 120 } \Omega.$$

$$\text{PHCN measures electrical energy in kilowatt-hours (kWh), where } 1 \text{ kWh = 1000 } \text{Wh.}$$

$$\text{The solenoid method gradually reduces the magnetic field by applying an alternating current through a solenoid.}$$

$$\text{At the equator, the magnetic field is horizontal, so the angle of dip is } 0^{\circ}.}$$

$$\text{The diagram represents a step-up transformer, which increases voltage and decreases current.}$$

$$\text{The electromotive force in the secondary winding varies depending on the transformer design and load.}$$

$$\text{This is a nuclear fusion reaction where two lighter nuclei combine to form a heavier nucleus and release energy.}$$

$$\text{During beta decay, a neutron is converted into a proton, so the atomic number increases by one.}$$

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

$$\text{Neon produces a pink glow in a discharge tube when an electric current passes through it.}$$

$$\text{The decay emits two alpha particles and two beta particles.}$$

$$\text{In a common emitter configuration, the output voltage is provided through the collector terminal.}$$

$$\text{The bond between silicon and germanium is covalent because they share electrons in their outer shells.}$$