Physics Jamb Formula

Physics JAMB Formulas: Essential Guide with Examples

Physics is a fundamental subject in the Joint Admissions and Matriculation Board (JAMB) examinations. Success in this subject often depends on a clear understanding of core formulas and their applications. This article highlights essential physics formulas for JAMB, explains their meanings, and provides examples to aid your preparation.

Key Physics Formulas for JAMB

1. Motion Formulas

Motion is a fundamental topic in physics. The following equations of motion are crucial for solving related problems:

Equations of motion:

First equation: \( v = u + at \)
Second equation: \( s = ut + \frac{1}{2}at^2 \)
Third equation: \( v^2 = u^2 + 2as \)

Where:

\( u \): Initial velocity (m/s)
\( v \): Final velocity (m/s)
\( a \): Acceleration (m/s²)
\( t \): Time (s)
\( s \): Displacement (m)

Example 1: Finding Final Velocity

Problem: A car starts from rest and accelerates uniformly at \( 3 \text{ m/s}^2 \) for 5 seconds. What is its final velocity?

Solution: Using \( v = u + at \):

\( v = 0 + (3 \times 5) = 15 \text{ m/s} \)

Answer: The final velocity is 15 m/s.

2. Work, Energy, and Power

Work Formula

Work done (\( W \)) is given by:

\( W = F \cdot d \cdot \cos(\theta) \)

Where:

\( F \): Force (N)
\( d \): Displacement (m)
\( \theta \): Angle between force and displacement

Energy Formulas

Kinetic Energy: \( KE = \frac{1}{2}mv^2 \)
Potential Energy: \( PE = mgh \)

Where:

\( m \): Mass (kg)
\( v \): Velocity (m/s)
\( g \): Acceleration due to gravity (9.8 m/s²)
\( h \): Height (m)

Power Formula

Power (\( P \)) is given by:

\( P = \frac{W}{t} \)

Where:

\( W \): Work done (J)
\( t \): Time (s)

Example 2: Calculating Work Done

Problem: A force of 20 N is applied to move an object 5 m along a straight line. What is the work done if the force is applied at an angle of 0 degrees?

Solution: Using \( W = F \cdot d \cdot \cos(\theta) \):

\( W = 20 \cdot 5 \cdot \cos(0) = 100 \text{ J} \)

Answer: The work done is 100 J.

3. Mechanical Advantage

In mechanics, simple machines help us perform work more efficiently. Key formulas include:

Mechanical Advantage (MA): \( MA = \frac{Load}{Effort} \)
Efficiency: \( \text{Efficiency} = \frac{Work_{output}}{Work_{input}} \times 100 \)

Example 3: Calculating Efficiency

Problem: A machine outputs 80 J of work after receiving 100 J of input work. What is its efficiency?

Solution: Using \( \text{Efficiency} = \frac{Work_{output}}{Work_{input}} \times 100 \):

\( \text{Efficiency} = \frac{80}{100} \times 100 = 80\% \)

Answer: The machine's efficiency is 80%.

Tips for Using Physics Formulas in JAMB

Memorize essential formulas and understand their derivations.
Practice solving past questions to familiarize yourself with common problem types.
Use diagrams to visualize problems, especially in mechanics and motion topics.
Review units and conversion factors to ensure accuracy in calculations.

Conclusion

Mastering physics formulas is vital for JAMB success. By understanding the formulas, practicing examples, and applying them to real-world scenarios, you can enhance your problem-solving skills and excel in your examination. Start practicing today and achieve your academic goals!