2022 - JAMB Physics Past Questions and Answers - page 1

A derived unit is a unit of measurement in the International System of Units (SI) that is derived from one or more of the seven base units.

Examples of derived units:

• Velocity (m/s)
• Density kg/m3
• Force (Newton)
• Pressure (Pascal)
• Energy (Joule)
• Power (Watt)

We can derive other units from the independent units. The independent units are called Fundamental Units (or Base Units).

Examples of fundamental units are Mass in kilogram (kg); Electric Current, ampere (A); Temperature, kelvin (K); Amount of Substance, mole (Mol).

When a bar magnet is cut into two, the newly cut faces will become the new north or south poles of the smaller pieces. Hence, the two cut pieces will have their own north and south poles. 

The wave equation is given by: y = 5mm sin \[1cm\\(^{-1}\\)x - 60s\\(^{-1}\\)t\]. The general form of a wave equation is: y = A sin(kx - ωt) where: * k is the wave number * ω is the angular frequency By comparing the given equation with the general form, the wave number (k) is the coefficient of x. Therefore, the wave number k = 1.0 cm\\(^{-1}\\)

Here's how to solve the problem: * **Understand the principle:** The pinhole camera creates similar triangles. The ratio of object height to image height is equal to the ratio of object distance to image distance. * **Set up the proportion:** (Object height) / (Image height) = (Object distance) / (Image distance) 40 cm / 20 cm = 30 cm / (Image distance) * **Solve for Image distance:** 2 = 30 cm / (Image distance) Image distance = 30 cm / 2 Image distance = 15 cm

No relative motion because when both the coil and the magnet are stationary there is no change in the magnetic flux hence, no current is induced in the coil.

Regular tires have treads which provide your tires with the ability to grip the road thereby enhancing traction. The tread also helps the vehicle to accelerate or decelerate, as well as to brake reliably.

Here's how to calculate the acceleration: 1. **Identify the knowns:** * Initial velocity (u) = 0 m/s (since the car starts from rest) * Distance (s) = 40 m * Time (t) = 10 s 2. **Choose the appropriate kinematic equation:** We can use the equation: s = ut + (1/2)at² 3. **Substitute the values and solve for acceleration (a):** * 40 = (0)(10) + (1/2) * a * (10)² * 40 = 0 + 50a * a = 40 / 50

 volumetric expansion (γ) = 3 x linear expansion

Local action defect caused by the impurities present in zinc rod.

The lost voltage (V_lost) in a cell is calculated using the formula: V_lost = I * r where: * I is the current flowing through the cell. * r is the internal resistance of the cell. Given: * I = 4 A * r = 0.55 Ω Therefore, V_lost = 4 A * 0.55 Ω = 2.20 V