EASY
Earn 100

Read the passage and answer the questions given below. 
Energy exists in the form of electricity in nature. There are many misconceptions regarding who discovered it. Many people credit Benjamin Franklin with the discovery of electricity. In reality, his experiments just proved that there exists a connection between electricity and lightning. 
Static electricity was thought to have been discovered by Ancient Greeks in about 600 BC, by rubbing fur on amber. English physician William Gilbert used the Latin term 'electricus' to describe the force of attraction exhibited by certain substances when rubbed together. Thomas Brown, another English scientist, used the word 'electricity' to describe his investigations based on Gilbert's work.
In 1752, Benjamin Franklin performed his experiment of flying a kite with a metal key in the presence of a storm. He conclusively proved that lightning and the tiny electric sparks were one and the same thing. In 1800, Italian physicist, Alessandro Volta constructed the voltaic pile, an early electric battery using chemical reactions producing electricity.
Answer the following question based on the passage.
Who are credited with the discovery of static electricity?

Important Questions on Electricity

MEDIUM

Write in brief the basic principle of hydroelectric power generation.

MEDIUM

What type of energy is transformed to electrical energy in a dynamo?

EASY
Write the names of three sources of direct current.
EASY

Answer the following:

What is the frequency of household alternating current (AC) in India?

MEDIUM
Explain the main principle of an electric generator by drawing a labelled diagram.
EASY
What is dynamo? Describe its method of working with a diagram.
MEDIUM
In a galvanic cell, the salt bridge
MEDIUM
Explain the underlying principle, working and uses of an electric generator with a labelled diagram.
MEDIUM
Explain with circuit diagram the parallel combination of identical cells. Obtain the condition for maximum current in the external resistance connected with the combination.
EASY
On which principle, electric generator works?
EASY
Two lamps, one rated 100 W; 220 V, and the other 60 W; 220 V, are connected in parallel to electric mains supply. Find the current drawn by two bulbs from the line, if the supply voltage is 220 V
EASY
The device used for producing electric current is called :
EASY
Give two differences between alternating current and direct current.
EASY
Which one of the following  alternating current is supplied in our house hold circuits?
EASY
The standard Gibbs energy for the given cell reaction in kJ mol-1 at 298 K is:
Zns+Cu2+aqZn2+aq+Cu(s) ,
E0=2 V at 298 K
(Faraday's constant ,F=96000 C mol-1)
HARD

For the cell Zn sZnSO4 aqCuSO4 aqCu s, when the concentration of Zn2+ is 10 times the concentration of Cu2+, the expression for ΔG in J mol-1 is

[F=Faraday's constant, R=universal gas constant, T=temperature, Eocell=1.1 V]

MEDIUM
Establish the relationship between electromotive force, terminal voltage and internal resistance.
EASY

Consider an electrical conductor connected across a potential difference V. Let Δq be a small charge moving through it in time Δt. If I is the electric current through it,
(i) the kinetic energy of the charge increases by IVΔt
(ii) the electric potential energy of the charge decreases by IVΔt.
(iii) the thermal energy of the conductor increases by IVΔt.

Then the correct statements is/are