What does the Snell’s law relate?
Light reflection
Light refraction
Light transmission
Light Absorption
On a sunny day you may see very bright lines formed on the bottom of a swimming pool. Why?
Absorption
Diffraction
Interference
Refraction
According to the electromagnetic wave model, when will produce visible light ?
an electric charge is accelerated with a magnitude within a given range.
an electric charge is moved at a constant velocity.
a blackbody is heated to any temperature above absolute zero.
an object absorbs electromagnetic radiation.
In the which of the following is most true for incoherent light.
the light waves are emitted randomly.
the light waves are in step with one another.
the light is said to carry information.
many different frequencies interact with one another to form a multi-dimensional picture.
Which of the following properties is a characteristic of the light waves from a laser?
The waves all have the same frequency
The waves are all in step with one another
The waves form a narrow beam
All of the above are true
Light appears to travel in a straight line because
wavelength of light is vey small
frequency of light is very small
light consists of very small particles
velocity is different for different colours
What is called the method of raising a particle from lower state to higher energy state?
Pumping
Pumping source
Population inversion
None of these.
What principle is responsible for light spreading as it passes through a narrow slit?
polarization
diffraction
refraction
interference
In which unit is the Planck’s constant expressed?
Joule
Joule-hertz
Joule-second
Newton-second
When does the phenomenon Luminescence happen?
Photons emit while excited electrons drops down
Knocking out of electrons by photons
Photons stimulated by photons
All
