Why is the use of ac voltage preferred over dc voltage? Given two reasons.

Explain the principle on which the working of a potentiometre is based. Why is the use of a potentiometer preferred over that of a voltmeter for measurement of e.m.f. of a cell?

What is the peak value of the voltage of a 220V ac line?

Answer the following Why is a mixture of helium and oxygen gas preferred over air for respiration during deep sea diving?

The teachers of Geeta's school took the students on a study trip to a power generating station, located nearly 200km away from the city. The teacher explained that electrical energy is transmitted over such a long distance to their city. In the form of alternating current (ac) raised to a high voltage. At the receiving end in the city, the voltage is reduced to operate the devices. As a result, the power loss is reduced. Geeta listened to the teacher and asked questions about how the ac is converted to a higher or lower voltage. Write two values each shown by the teachers and geeta,

Why is paracetamol preferred over aspirin as an antipyretic?

Why is molality preferred over molarity State Kohlrausch's law of independent migration.

An LCR circuit (R=40Omega,L=100mH,C=0.242muF) is connected with an ac voltage source of peak voltage 200 V and frequency 1000 Hz.