A Manual of Physical Measurements |
Common terms and phrases
adjusted ammeter ampere angle axis ballistic galvanometer battery calculated calorimeter centimeter charge collimator compute condenser constant cross-hairs curve cylinder deflection determined difference of potential diffraction grating disc discharge distance dynes electromotive force electroscope equal equation error EXPERIMENT eye-piece fall of potential figure of merit galvanometer circuit glass gram high resistance inductance coil inductor joules length lens lines of force magnetic field magnetometer mass means measured mercury meter METHOD Apparatus micrometer mirror moving mutual induction needle null point number of lines object observed obtained parallax parallel perpendicular placed plane pole position poundal pressure prism quantity of electricity R₁ ratio rays reading Rotate the analyzer scale screw shown in Fig solenoid spectrometer spherometer sq.cm sq.in standard cell tangent galvanometer telescope temperature thermometer throw tion torsion tube unit velocity vernier vertical vibrations voltmeter wave plate weight wire zero
Popular passages
Page 231 - As a unit of resistance, the international ohm, which is based upon the ohm equal to 10" units of resistance of the CGS system of electromagnetic units, and is represented by the resistance offered to an unvarying electric current by a column of mercury at the temperature of melting ice, 14.4521 grams in mass, of a constant cross-sectional area and of the length of 106.3 centimetres.
Page 231 - The international ampere is the unvarying electric current which, when passed through a solution of nitrate of silver in water, in accordance with the Specification II attached to these Resolutions, deposits silver at the rate of 0.00111800 of a gram per second.
Page 230 - Henry, which is the induction in a circuit when the electro-motive force induced in this circuit is one international volt while the inducing current varies at the rate of one Ampere per second.
Page 231 - As a unit of electromotive force, the international volt, which is the electromotive force that, steadily applied to a conductor whose resistance is one international ohm, will produce a current of one international ampere...
Page 231 - As a system of units representing the above and sufficiently near to them to be adopted for the purpose of electrical measurements and as a basis for legislation...
Page 152 - EMF of one volt when the current is changing at the rate of one ampere per second.
Page 134 - A well constructed (Pool's) mercury-and-rocker commutator may be employed to accomplish the same result. The cross-bars are removed and connections made as shown in Fig. 3. The height of the mercury in the cups is adjusted so that when the rocker is turned from the charging position, shown in the figure, the cell circuit is opened first, at cup I. The rocker then makes a contact in cup 2 before leaving cup 3, discharging the condenser during the time the two cups are in connection. The period of...
Page 22 - M (g-ar) where g is the acceleration of gravity and r is the radius of the disc on which the string supporting the weight is wound.
Page 163 - It contains two coils without iron joined in series, one of them fixed and the other movable about a vertical axis. The selfinduction of the two depends upon their relative position, and the scale at the top is graduated to read in millihenrys.
Page 118 - Use the sign + or — to show whether the correction is to be added to or subtracted from the observed reading.