Physics – Force and Motion

Simple Pendulum Laws

- Law of Mass: The time of oscillation does not depend on the mass of the bob.  

- Law of Amplitude: Time of oscillation does not depend on amplitude.  

- Nature of Material: The time of oscillation does not depend on the material of the bob.  

- Law of Length: Time of oscillation depends on the length of the pendulum (longer pendulum = slower oscillation).  

Newton’s Laws of Motion

1. First Law (Law of Inertia): An object remains at rest or in uniform motion unless acted upon by an unbalanced force.  

2. Second Law: Acceleration depends on both the net force acting on the object and its mass.  

3. Third Law: For every action, there is an equal and opposite reaction.  

Pendulum Terms

- Point of suspension: The point where the pendulum hangs.  

- Length of pendulum: Distance between the point of suspension and the centre of the bob.  

- Amplitude: Maximum displacement from the mean position to the extreme position.  

- Point of oscillation: The centre of the mean position.  

- Mean position: The central resting position of the pendulum.  

- Extreme position: The farthest point reached on either side during oscillation.  

Rest and Motion

- Rest: When an object is not moving.  

- Motion: When an object is moving.  

Types of Motion

- Oscillatory motion: Back and forth movement (e.g., swing).  

- Vibratory motion: To and fro movement in a fixed position; body remains fixed (e.g., guitar string).  

- Periodic motion: Repeated motion at regular intervals (e.g., clock pendulum, heartbeat).  

- Uniform motion: Equal distance covered in equal intervals of time along the same path (e.g., car moving at constant speed).