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AimTo determine the velocity of a pulse propagated through a stretched string/slinky.
Apparatus RequiredA slinky with flat wire made up of metal or plastic should be at least 1 m long, a meter scale, a stop-watch, a marker or chalk.
TheoryWave: A wave is a phenomenon that transfers energy through a medium or space without the physical transfer of matter. Waves can be characterized by their amplitude, frequency, wavelength, and velocity. They can be described by a mathematical function, such as a sine wave or cosine wave. Waves can be found in many forms, including light, sound, and water waves. The behavior of waves is governed by the principles of wave mechanics, which describe how waves propagate, interact, and interfere with each other.
SlinkyA slinky is a toy made of a long, thin, flexible spring that can stretch and compress. The spring is typically made of metal or plastic, and it can be coiled up into a compact shape or stretched out to several feet in length. When a slinky is compressed or stretched, it stores potential energy that can be released when it is allowed to return to its original shape. This can create a variety of interesting behaviors, such as a slinky “walking” down stairs, or waves of compression and expansion traveling along the length of the spring. Slinkies are often used as educational toys to teach children about concepts such as elasticity, potential energy, and wave propagation.
Pulse: A pulse is a single disturbance or vibration that travels through a medium, creating a wave that propagates away from the source of the disturbance. Pulses can be created by a variety of means, such as a sudden pressure change, a mechanical shock, or a sudden displacement of a medium. Pulses can be characterized by their amplitude, duration, and shape, and they can be used to transmit information or signals through a medium. Examples of pulses include sound waves produced by a clap of the hands, water waves produced by a splash, or light pulses produced by a laser. In contrast to continuous waves, which are characterized by a continuous oscillation, pulses are discrete events that occur at a specific moment in time.
Procedure1 .The procedure involves marking a point on the floor of a long corridor and measuring the distance of 1 m from that point using a meter scale, marking it as point Q.
2 .One student holds one end of a slinky at point P, while another student stretches the slinky and brings it to point Q.
3 .A third student holds a stopwatch.
4 .The student who stretched the slinky pushes it sharply towards point Q, stopping at point Q, which creates a pulse in the slinky that travels towards point P and gets reflected back towards point Q.
5 .The time from the push at point Q to the pulse traveling towards point P and back to point Q is recorded.
6 .This process is repeated 56 times, and observations are recorded. The velocity of the pulse is calculated using a formula.