Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
- Name an instrument that measures electric current in a circuit.
Define the unit of electric current. - What do the following symbols mean in circuit diagrams?
- An electric circuit consisting of a 0.5 m long nichrome wire XY
Define the unit of electric current.
(a) An instrument that measures electric current in a circuit is called an "ammeter". The unit of electric current is ampere (A). 1 ampere is constituted by the flow of 1 coulomb of charge through any point in an electric circuit in 1 second.
(b) The following symbols mean in circuit diagrams are:
(i) Variable resistance or Rheostat.
(ii) Plug key or switch (closed).
(c) (I)
(c) (ii) Following graph was plotted between $V$ and $I$ values:
At potential difference $0.8\ V$,
$\frac {V}{I}=$\frac {0.8}{0.3}=$\frac {8}{3}$
At potential difference $1.2\ V$,
$\frac {V}{I}=$\frac {1.2}{0.45}=$\frac {8}{3}$
At potential difference $1.6\ V$,
$\frac {V}{I}=$\frac {1.6}{0.6}=$\frac {8}{3}$
Conclusion: If $I$ be the current through $XY$ resistor and $V$ be the potential difference across it, then the ratio $\frac {V}{I}=constant$.
$\Rightarrow V\propto I$, and Ohm's law is obeyed.
42 Views
