Q14DQ - University Physics with Modern Physics

Question

Energy can be transferred along a string by wave motion. However, in a standing wave on a string, no energy can ever be transferred past a node. Why not?

Step-by-Step Solution

Answer

There is no transfer of energy in the standing wave passing the node

STEP1: Kinetic energy concept.

A sort of energy that an element or particle possesses as a result of its movement is known as kinetic energy.

The expression for the kinetic energy can be written as: 

$\mathrm{KE}=\frac{1}{2}{\mathrm{mv}}^2$ 

Here, m is the mass of the object and v is the velocity of the object. 

The kinetic energy of an object can be calculated by examining the mass and velocity of the object. It varies linearly with the velocity of the object. Hence, as the object's velocity increases, the object's kinetic energy also increases.

STEP 2: Relation of Transfer of energy with nodes and antinodes .

Energy can be transferred along a string as a result of the wave's motion. However, it is not possible in a standing wave on a string because the two waves that create it would each carry roughly equal amounts of power in various directions. 

Standing waves have limited energy mobility from each node to the surrounding antinodes and back, but the average rate of energy transfer is always zero.