Question
What is AC current and DC current? Why is AC voltage preferred compared to DC voltage in practice?
✓
Answer
→AC current : The current that varies like a sine or cosine function with time is called AC current.
→DC current : The current that remains constant with time is called DC current.
→AC voltage is preferred more than DC voltage in practice, because...
(1) Using transformers, the value of AC voltage can be changed easily.
(2) Electrical energy can be transmitted economically (and easily) over long distances.
→DC current : The current that remains constant with time is called DC current.
→AC voltage is preferred more than DC voltage in practice, because...
(1) Using transformers, the value of AC voltage can be changed easily.
(2) Electrical energy can be transmitted economically (and easily) over long distances.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Can a vector have zero component along a line and still have nonzero magnitude?
A capacitor with capacitance C is changed to potential V. What is its electrical energy ?
A circular loop of one turn carries a current of 5.00A. If the magnetic field B at the centre is 0.200mT find the radius of the loop.
What kind of ferromagnetic material is used for coating magnetic tapes in a cassette player or for building memory stores in a modern computer?
Lithium (Z = 3) has two stable isotopes 6Li and 7Li. When neutrons are bombarded on lithium sample, electrons and $\alpha$-particles are ejected. Write down the nuclear process taking place.
→Provide the classification of semi-conductors with example.
- Write the necessary conditions for the phenomenon of total internal reflection to occur.
- Write the relation between the refractive index and critical angle for a given pair of optical media.
The radius of the innermost electron orbit of a hydrogen atom is 5.3 ×10-11 m. What are the radii of the n = 2 and n = 3 orbits?
Let $\vec{\text{a}}=4\vec{\text{i}}+3\vec{\text{j}}$ and $\vec{\text{b}}=3\vec{\text{i}}+4\vec{\text{j}}.$ (a) Find the magnitudes of:
→-
$\vec{\text{a}}$
-
$\vec{\text{b}}$
-
$\vec{\text{a}}+\vec{\text{b}}$
-
$\vec{\text{a}}-\vec{\text{b}}$
Consider a gravity-free hall in which a tray of mass M, carrying a cubical block of ice of mass m and edge L, is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descend?
