Waves

• When a load is hung on the spring, it stretches and the spring's extension is proportional to the weight of the object.
• The working principle of the spring balance is Hooke's law which is F=-kx.

• It also demonstrates a type of periodic motion called simple harmonic motion (SHM), especially when the displacement from the equilibrium is small.

The time period of a simple pendulum is given by the formula:

where:

$T$ is the time period
$l$ is the length of the pendulum
$g$ is the acceleration due to gravity

• This formula shows that the time period depends only on the length of the pendulum and the acceleration due to gravity.
• It does not depend on the mass of the bob or the amplitude of the swing (for small angles).
• If a pendulum oscillates in a vacuum, the absence of air resistance means there is no damping force acting on the pendulum to slow down its motion.
• However, the fundamental forces that determine the time period – gravity and the length of the pendulum – remain unchanged.
• Therefore, the time period of a pendulum oscillating in a vacuum will be the same as if it were oscillating in the air (assuming negligible air resistance in the latter case).
• The vacuum only eliminates the gradual decrease in amplitude over time due to air friction, allowing the oscillations to continue indefinitely with a constant period.

The spring of a clock, when wound, possesses potential energy, specifically elastic potential energy.

Winding the clock: When you wind a clock, you are applying a force to twist the spring. This action stores energy in the spring by changing its shape (coiling it tighter).

Stored energy: This stored energy is potential energy because it has the potential to do work. In this case, the potential energy is due to the elastic nature of the spring material, which resists being twisted. Hence, it's called elastic potential energy.

Releasing energy: As the clock unwinds, this stored elastic potential energy is gradually released, powering the gears and hands of the clock. The potential energy is converted into kinetic energy (the energy of motion) of the clock's components.

• The angle subtended by any two points at any position is useful for measuring with sufficient accuracy.
• Due to these characteristics, sextants are used by sailors for navigation.

1. intensity,
2. pitch,
3. and quality.

The intensity of sound depends on the amplitude of the vibration.

Its S.I unit is watt per square meter (W/m²).

The SI unit for frequency is the hertz (Hz).

• One hertz is defined as one cycle per second.
• In other words, if an event repeats itself at a rate of one time per second, then its frequency is 1 Hz.
• The hertz is named after Heinrich Hertz, a German physicist who made significant contributions to the study of electromagnetic waves.

• The intensity of sound depends on the amplitude of vibration of the vibrating body producing the sound.
• The greater the amplitude of vibration, the greater will be the intensity of the sound.

• The intensity of sound depends on the amplitude of vibration of the vibrating body producing the sound.
• The greater the amplitude of vibration, the greater will be the intensity of the sound.

• The intensity of sound depends on the amplitude of vibration of the vibrating body producing the sound.
• The greater the amplitude of vibration, the greater will be the intensity of the sound.