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Explanation: 2 Marks
Diagram: 1 Mark
In the given circuit, the positive terminals of both the batteries are joined together so there is no flow of current and hence the bulb didn't glow.
The current flows from positive terminals, therefore, the positive terminals of the cell will be connected to negative terminal of the cell and vice versa.
Current always flows from the positive terminal to the negative terminal.

:
Statement: 1 Mark
Reason: 2 Marks
An electromagnet cannot be used for separating plastic bags from a garbage heap. This is because plastic bags are non-magnetic materials and electromagnet is used to separate only the magnetic materials.
Scrap iron can be separated from the heap, as it is a magnetic material. So, if we use an electromagnet, it can separate iron scraps from the heap.

:
(a) Diagram: 2 Marks
(b) Explanation: 3 Marks
(a)

(b) No, the electrician cannot be allowed to replace the fuse in the house by a piece of wire because every wire cannot be used as a fuse filament. A fuse filament must have a low melting point such that it could melt and break in response to a large amount of current. Most of the wires have high melting points.

Answer: Option A. -> True
:
A
A switch prevents or allowscurrent to flow through it. It isa device for making and breaking connections in an electric circuit.

Answer: Option D. -> Live wire
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D
Live wire or phase wire is usually covered with red insulation. The neutral wire has a black insulation whereas the earth wire is insulated by a green or a yellow insulation.

Answer: Option D. -> (ii), (iii), (i)
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D
Electric bell works on the magnetic effect of electric current. An electric bell consists of an electromagnet, a striker and a gong. When the circuit is closed, the electromagnet attracts the striker towards it. The striker hits the gong and produces a sound.When the striker hits the gong, the circuit is broken and theelectromagnet loses its magnetism. The spring arm restores the striker to its original position. As soon as contact is established the same process is repeated.

Answer: Option C. -> positive terminal to the negative terminal
:
C
In an electric circuit, the conventional direction of the current is taken as from the positive terminal to the negative terminal. Because earlier it was believed that the protons are responsible for electric current. Eventually, we found that the electrons are responsible for electric current. Electrons are free to move and the flow of electrons is from negative to the positive terminal. The direction of an electric current by convention is the direction in which a positive charge would move.

Answer: Option B. -> False
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B
The long line in the symbol of an electric cell represents its positive terminal and the short line represents its negative terminal.

Answer: Option B. -> battery
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B
A battery is definedas a container consisting of one or more cells, in which chemical energy is converted into electricity and used as a source of power.

Answer: Option C. -> negatively charged
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C
Electrons are the negativelychargedparticles of an atom. The negativecharge of electrons in the orbitals of an atom balances the positive charge of the protons in the atomic nucleus. They are extremelysmallcompared to all the other parts of the atom. The mass of an electron is almost $1837$ times less than the mass of a proton.