Explanation

• V=f/λ is an expression that holds good for wave velocity
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• The wave velocity of a wave is given by v=fλ 
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• lambda = refers to the wavelength, the distance between the crests in meters (m)
• v = refers to the velocity of the speed of waves moving in a direction in meters per second (m/s)
• f = refers to the frequency, the wave crests that go through a point in certain time cycles per second or hertz (cycles/s or Hz)

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  RY 23-12-2022

  
  

Explanation

A bolometer is a device for measuring radiant heat by means of a material having a temperature-dependent electrical resistance.

Bolometer was invented in 1878 by Samuel Pierpont Langley (American astronomer)

Explanation

In solids, heat transfer occurs primarily through conduction, where vibrations and collisions of particles (atoms or molecules) transfer energy from one point to another.

Explanation

Explanation

• The Candela (cd) is the SI unit of luminous intensity.
• It is defined as the luminous intensity of a monochromatic source that emits light at a frequency of 540 x 10^12 Hz with a luminous efficiency of 683 lm/W.

Explanation

Wavelength is a measure of distance between two wave crests or troughs.

The SI unit for measuring distance is the meter (m), hence it is used for wavelength.

It is typically denoted by the symbol λ (lambda).

Explanation

• The principal axis is a horizontal line that passes through the centre of the lens, perpendicular to its surface.
• It is the central axis around which the lens is symmetrical.

Explanation

A magnifying glass uses a convex lens to enlarge the appearance of objects.

Convex lenses converge light rays to a focal point, producing a magnified image.

Explanation

• The formula of Density is: D=m/v
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• Here D is density,
• M is mass &
• V is Volume.
• Density is commonly expressed in units of grams per cubic centimeter.
• The standard units are kg/m³
  

Explanation