Elementary Lessons in Heat, Light and Sound |
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amount of heat angle of incidence antinode beam body boiling boiling-point bulb called calorimeter candle centre of curvature coefficient coil coloured concave lens concave mirror condensation convex lens cooling cork distance diverge equal equation evaporation EXAMPLES ON CHAPTER expansion EXPT flame flask focal length front given glass tube grammes heat required hole image and object image is formed inches incident ray increases index of refraction interval inverted iron lamp-black latent heat lenses liquid longitudinal waves measured melting mercury normal observer optical parallel passes path perpendicular pipe placed position pressure principal axis principal focus prism produced pulse of rarefaction radiation ray of light real image reflected refracted ray screen shown in Fig side source of light specific heat spiral steam string surface temperature thermometer travels vapour vertical vessel vibration vibration-number virtual image volume warm water-vapour wave-length waves weight wire
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Page 42 - It will be seen from the above definition that the specific heat of a substance is the ratio between the amount of heat required to raise the temperature of the substance 1°, and the amount of heat required to raise the temperature of the seme weight of water 1°.
Page 211 - ... of light falls upon a concave lens. Trace the position of the image as the point of convergence of the pencil moves from an infinite distance up to the lens. 24. What is meant by the statement — the focal length of a given convex lens is 2 feet ? Draw a figure, approximately to scale, indicating the paths of the rays of light and the positions of the images formed, when an object is placed (a) at a distance of 6 feet, (6) at a distance of 1 foot from such a lens.
Page 146 - MIRRORS). 1. Given the law of reflexion, prove that the image of an object in a plane mirror is on the perpendicular to the mirror and as far behind as the object is in front. 2. When a horizontal beam of light falls on a vertical plane mirror which revolves about a vertical axis in its plane, shew that the reflected beam revolves at twice the rate of the mirror.
Page 147 - A candle is placed at a given small distance in front of an ordinary looking-glass made of thick plate-glass quick-silvered on the back, and a person looking obliquely into the mirror sees several images of the candle ; explain this, and show the exact positions of the images by a diagram.
Page 148 - The following definitions apply equally to concave and convex mirrors: The middle point of the mirror is called its vertex. The centre of the sphere, of which the mirror forms a part, is called the optical centre.
Page 268 - Ibs., vibrates 100 times per second when plucked. If I wish to make two yards of the same wire vibrate twice as fast, with what weight must I stretch it * 5.
Page 30 - Again, the volume of a given mass of gas is inversely proportional to its...
Page 47 - What is meant by saying that the specific heat of water is 30 times as great as that of mercury? If a pound of boiling water is mixed with a pound of ice-cold mercury, what will be the temperature of the mixture ? 4.
Page 149 - The plane which contains the incident and reflected rays and the normal to the surface is called the plane of incidence, the angle between the incident ray and the normal is the angle of incidence...
Page 190 - ... lowest face is over a black spot on the paper. Draw and explain diagrams to illustrate the apparent position of the spot to an observer looking at it (1) through the top, (2) through one of the side faces of the cube.