2024 - JAMB Physics Past Questions and Answers - page 1

Here's how to solve this problem: 1. **Calculate the volume of the rectangular solid:** * Volume (V) = length × breadth × height * V = 10 cm × 5 cm × 2 cm = 100 cm³ * Convert cm³ to m³: 100 cm³ × (1 m / 100 cm)³ = 100 × 10⁻⁶ m³ = 1 × 10⁻⁴ m³ 2. **Calculate the mass of the solid:** * Density (ρ) = mass (m) / volume (V) * m = ρ × V * m = 100 kg/m³ × 1 × 10⁻⁴ m³ = 0.01 kg 3. **Calculate the weight (force) of the solid:** * Weight (W) = mass (m) × acceleration due to gravity (g) * Assume g = 10 m/s² * W = 0.01 kg × 10 m/s² = 0.1 N 4. **Determine the area in contact with the surface:** * The solid lies on a horizontal surface, so the area in contact is the area of the base. We need to consider the different possible orientations. The question doesn't specify which face is in contact. Assuming the base is the 10cm x 5cm face: * Area (A) = length × breadth * A = 10 cm × 5 cm = 50 cm² * Convert cm² to m²: 50 cm² × (1 m / 100 cm)² = 50 × 10⁻⁴ m² = 5 × 10⁻³ m² 5. **Calculate the pressure:** * Pressure (P) = Force (W) / Area (A) * P = 0.1 N / 5 × 10⁻³ m² = 20 N/m² * The base could also be 10cm x 2cm, giving an area of 20cm². P = 0.1 / (2 x 10^-3) = 50 N/m² * The base could also be 5cm x 2cm, giving an area of 10cm². P = 0.1 / (1 x 10^-3) = 100 N/m² Since the only possible answer that's close to one of the above calculations is 100 N/m², and the question doesn't specify what orientation it lies on, C must be the correct option.

Work is done when a force causes a displacement. * **A:** The man is applying a force, but there is no displacement of the load (it remains stationary). * **B:** The woman applies a force, but there's no displacement. * **C:** The boy applies a force to climb, and there is a displacement in the vertical direction. Thus, work is done. * **D:** The man applies a force, but the tanker does not move (no displacement).

* **Acceleration** is defined as the rate of change of velocity.* **Velocity** includes both speed and direction.* Therefore, when a bus is accelerating, it must be changing its velocity. This change can involve a change in speed, a change in direction, or both.

The relationship between real depth (actual depth) and apparent depth is given by the refractive index formula: Refractive index (n) = Real depth / Apparent depth We are given: * Apparent depth = 10 cm * Refractive index of water (n) = 1.33 We need to find the real depth. Rearranging the formula: Real depth = Refractive index × Apparent depth Real depth = 1.33 × 10 cm Real depth = 13.3 cm

Here's how to solve this problem: 1. **Understand the Circuit:** The circuit appears to be a Wheatstone bridge configuration. The galvanometer is in the middle branch. 2. **Wheatstone Bridge Balance Condition:** For the galvanometer to measure 2A, there must be a current flowing through the galvanometer, which implies that the bridge is not balanced. 3. **Analyze the Circuit:** The problem states that the galvanometer measures 2A. Since the galvanometer isn't measuring zero current, the Wheatstone bridge is not balanced. We would need more information to determine the exact value of R based only on the information that the galvanometer measures 2A. However, since the question asks for *a* value, let us assume an ideal case. 4. **Solve for R:** If

The power of a lens is the reciprocal of its focal length in meters. Here's how to solve the problem: 1. **Convert focal length to meters:** 20 cm = 0.20 m 2. **Calculate power:** Power (P) = 1 / focal length (f) = 1 / 0.20 m = 5.0 D (diopters)

The energy of a moving car is primarily due to its motion.* **Kinetic energy** is the energy an object possesses due to its motion.* **Mechanical energy** is the sum of potential and kinetic energy. While the car possesses mechanical energy, the primary form of energy in motion is kinetic.* **Electrical energy** involves the flow of electric charge, not relevant to a car's motion directly.* **Potential energy** is stored energy due to position or condition, not motion.

A concave mirror is the best choice for a shaving mirror because it can produce a magnified, upright image when the object (your face) is placed within the focal length of the mirror. This magnification makes it easier to see details and perform tasks like shaving. Convex mirrors produce diminished images, and plane mirrors produce images the same size as the object. Parabolic mirrors are used for focusing light, not for image magnification in this context.

Here's how to solve the problem: 1. **Identify the formula:** The heat energy (Q) released or absorbed is calculated using the formula: Q = mcΔT where: * m = mass of the substance * c = specific heat capacity * ΔT = change in temperature (T_final - T_initial) 2. **Convert units if necessary:** * Mass (m) is given in grams (g), but the specific heat capacity is in kg. Convert the mass to kilograms: m = 60g = 60/1000 kg = 0.06 kg 3. **Identify the values:** * m = 0.0

Here's how to solve this problem: 1. **Identify the formula:** The energy of a photon is given by E = hc/λ, where: * E = energy of the photon * h = Planck's constant (6.63 x 10⁻³⁴ Js) * c = speed of light (3.0 x 10⁸ m/s) * λ = wavelength (5.68 x 10⁻⁶ m) 2. **Plug in the values:** E = (6.63 x 10⁻³⁴ Js * 3.0 x 10⁸ m/s) / 5.68 x 10⁻⁶ m 3.