Tnpsc and Upsc Notes Pdf
Pravin Babu RTotal Internal Reflection When the angle of incidence in the denser medium increases the angle of refraction also increases and it reaches a maximum value of r = 90° for a particular angle of incidence value. This angle of incidence is called the critical angle. The angle of incidence at which the angle of refraction … Read more
Speed of light Speed of Light in Different Media Substance Speed of light (ms-1) Refractive Index (𝝁) Water 2.25 x 108 1.33 Glass 2 x 108 1.5 Diamond 1.25 x 108 2.41 Air 3 x 108 1 Refractive Index and Speed of Light in different Medium Note: The refractive index of a medium is also … Read more
Curved Mirrors There are many types of curved mirrors such as spherical and parabolic mirrors. The most widely used curve is a spherical mirror. The hemispherical spoon is also a curved mirror, it has an inner and outer surface. One side of the spoon is a concave mirror and another side is a convex mirror. … Read more
Refraction of Light When the light is from one medium to medium with different optical densities, the path of light gets bent or deviated from the original path. This phenomenon is called the Refraction of Light. Causes of Refraction of Light Light rays get deviated from the original path when entering into another medium with … Read more
The parallel rays of light from the sun are focussed at a point using a concave mirror which is used to burn paper from the above diagram. In the concave mirror, as we bring the object closer, the image gets bigger. An Erected Magnified image is seen. At some positions, there is no image that … Read more
Convex Mirror Laws from Convex Mirror Law 1: A ray of light which is parallel to the optic axis or principal axis of a convex mirror seems to be coming from its principal focus after reflection from the mirror. Law 2: A ray of light going towards the centre of curvature is reflected along the … Read more
Characteristics of Sound WaveThere are five characteristics of sound. They are: Speed or Velocity, Amplitude, Frequency, period, Wavelength Figure 2: Characteristics of Sound Wave Amplitude(A) Amplitude is the displacement of the particle of the medium from its original position when the wave is passed through it. If the displacement of the particle is maximum, it … Read more
Ultrasonic or Ultrasound The sound waves greater than 20,000 Hz is called ultrasonic sound. Humans cannot hear ultrasound and some animals can hear. Ex: Dogs, Deer etc. Ultrasonic whistles are used in vehicles such as cars to alert Deers that cross the roads. Ultrasonics has an important application in the medical field. It is used … Read more
The ear is a sensitive organ used to hear. It converts the pressure variations in the air with audible frequencies into electric signals sent through the auditory nerve to the brain. The outer ear is known as Pinna. Pinna collects the sound. Then it travels via the auditory canal. At the auditory canal end, there … Read more
Christian Doppler (1803-1853), observed that the sound received by a listener is different from the original frequency produced when there is relative motion between the source and the receiver. What is the doppler effect? That is whenever the listener or source moves the frequency is changed from the original. This is called the Doppler effect. … Read more