Question
Distinguish between mechanical and electromagnetic waves.

Answer

Electromagnetic wavesMechanical waves
1. They can travel in vacuum.1. They cannot travel in vacuum. They need a materia I medium for their propagation.
2. These are formed by the periodic vibrations of mutually perpendicular electric and magnetic field in a plane normal to the direction of wave propagation.2. These are formed by the vibrations of the medium particles about their mean positions. These vibrations can be along the direction of propagation of wave or perpendicular to it..
3. These are traverse in nature.3. These waves can be transverse as well as IonqitudnaI.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Name any two electromagnetic waves which have a frequency higher than that of violet light. State one use of each.
A molten metal of mass $150 g$ is kept at its melting point $800^{\circ} C$. When it is allowed to freeze at the same temperature, it gives out $75,000 J$ of heat energy.
(a) What is the specific latent heat of the metal?
(b) If the specific heat capacity of metal is $200 Jkg ^{-1} K ^{-1}$, how much additional heat energy will the metal give out in cooling to $-50^{\circ} C$ ?

Obtain an expression for the potential energy of a body of mass m at a height h above the ground.
The rearview mirror of a motorbike starts vibrating violently at some particular speed of the motorbike, what could be done to stop the violent vibrations.
Name two main sources of nuclear radiations. How are these radiations harmful?
What is the equivalent resistance between A and B in the given circuit (Fig?)

Image

Fig 3.19 below shows a wheel barrow of mass $15 kg$ carrying a load of $30 kgf$ with its centre of gravity at A. The points B and C are the centre of wheel and tip of the handle such that the horizontal distance $A B=20 cm$ and $A C=40 cm$.



Calculate: (i) the load arm, (ii) the effort arm, (iii) the mechanical advantage and (iv) the minimum effort required to keep the leg just off the ground.
shows a uniform metre scale of weight W supported on a fulcrum at the 60 cm mark by applying the effort E at the 90 cm mark.
(a) state with reason whether the weight W of the scale is greater than, less than or equal to the effort E.
(b) Find the mechanical advantage in an ideal case.

What happens to the (i) atomic number, (ii) mass number of an element when (a) α - particle (b) β -particle and (c) γ -radiation are emitted?
A wire is passed through a piece of cardboard as shown in fig .. An electric current flows vertically down the wire and then flows back up. The two sections of the write are observed to repel each other.
(a) Wi th the aid of a diagram, describe how you would plot the magnetic field lines on the card .

Image

(b) Sketch the magnetic field patterns around both the sections of the wire. Use your sketch to explain why the two sections repel each other.
(c) The repulsive force between the two sections is small. What changes could be made to increase it?