A potentiometer is an accurate and versatile device to make electrical measurements of emf because the method involves a condition of no current flow through the galvanometer, the device can be used to measure potential difference, internal resistance of a cell and compare emf's of two sources. Q.

The columns are a correct match.

I. Electric current            - Ampere

II. Potential difference    -   c. Volt

III. Gapacitance               -   b. Farad   

IV. inductance                 -   a. Henryd.

1. Mechanical energy is a combination of kinetic energy and potential energy.

2. Mechanical energy is defined as the sum of kinetic energy and potential energy used to do work on an object.

3. Mechanical energy is the form of energy that is related to the position and motion of an object.

If the observer is moving away from the source ((Figure)), the observed frequency can be found: λs=vTo−voTovTs=(v−vo)Tov(1fs)=(v−vo)(1fo)fo=fs(v−vov).

Explanation: Most communication waves cannot transmit data accurately over long distances due to the curvature of the earth. They can only do so in the line of sight. However, they are not reflected by the ionosphere like radio waves and can be relayed to a wide area using geostationary satellites.

A real gas can behave as an ideal gas if volume of molecule is negligible and interaction between molecule is negligible. This will happen if number of molecule per unit volume is very small. This is only possible at high temperature and low pressure.