What is electric current question answer?
What is electric current question answer?
Electric current is defined as the rate of flow of negative charges of the conductor. In other words, the continuous flow of electrons in an electric circuit is called an electric current. The conducting material consists a large number of free electrons which move from one atom to the other at random.
When the resistance of a circuit increases the current will?
As the resistance increases, the current decreases, provided all other factors are kept constant. Materials with low resistance, metals for example, are called electrical conductors and allow electricity to flow easily.
What are the 3 types of electrical currents?
With direct current, electrons move in one direction. Batteries produce direct current. In alternating current, electrons flow in both directions. Power plants produce AC electric current.
What is the SI unit of electric current?
ampere (A)
Unit of electric current: ampere (A) The ampere, symbol A, is the SI unit of electric current. It is defined by taking the fixed numerical value of the elementary charge e to be 1.602 176 634 ×10−19 when expressed in the unit C, which is equal to A s, where the second is defined in terms of ∆νCs.
What is correct formula for resistance?
R = V ÷ I Question What is the resistance of the lamp? To calculate the resistance of an electrical component, an ammeter is used to measure the current and a voltmeter to measure the potential difference. The resistance can then be calculated using Ohm’s Law.
Does temperature affect resistance?
If the temperature of a metal conductor increases, the ions of the metal vibrate more vigorously. This increases the number of collisions between the free electrons and the ions. Hence, for a metal, resistance increases with increasing temperature. Often the increase in temperature is caused by an increase in current.
Why does resistance increase when current decreases?
The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance. The resistance of a long wire is greater than the resistance of a short wire because electrons collide with more ions as they pass through.
How is current produced?
To produce an electric current, three things are needed: a supply of electric charges (electrons) which are free to flow, some form of push to move the charges through the circuit and a pathway to carry the charges. The pathway to carry the charges is usually a copper wire.
What is symbol for current?
symbol I
Current is usually denoted by the symbol I. Ohm’s law relates the current flowing through a conductor to the voltage V and resistance R; that is, V = IR. An alternative statement of Ohm’s law is I = V/R.