8. Compare the power used in in each of the following;
a) 6-volt battery in series with 1 ohm and 2-ohm resistors.
b) 4-volt battery in parallel with 12 ohm and 2-ohm resistors.
IV. Answer the following questions: 3x3=9
9. Draw a neat diagram of electric motor and label carbon brushes and split rings.
10. Explain an experiment to show convex lens converges light rays.
OR
i) Refractive index of a benzene is 1.50. What does it mean?
ii) In which direction the light bends when it moves from air into benzene solution?
11. What is a solar cell? List out the uses of solar cell and its limitations.
V. Answer the following questions: 4x2=8
12. i) How fuse is helpful in domestic electric circuits?
ii) Why does the cord of an electric heater not glow while the heating element does?
13. a) Name the rule used to find direction of induced current in generator and define it.
b) How can we increase electric current in generator?
OR
Write the construction and working of a generator.
Answers
Answer:
Q8 campare the following
(a) sorry i dont khon the answer of this ques
(b)12 Ohm and 2 Ohm resistors are connected in parallel. The voltage across each component of a parallel circuit remains the same. Hence, the voltage across 2 Ohm resistor will be 4 V. Therefore, the power used by 2 Ohm resistor is 8 W.
Q9 diagram in above
Q10.explain:
A convex lens can be regarded as made of a very large number of portions of triangular prisms. The bases of these prisms are towards the central thicker portion of the lens.
(2) A ray of light passing through a prism bends towards its base. Hence, a convex lens converges the rays falling on it.
Q11.The actual solar cells are made of silicon semiconductors that absorb sunlight and then convert it into electricity. Currently, solar panels that are used for domestic purposes are only able to take around 20% of the sunlight that they receive and turn it into electricity. This is what is known as solar efficiency.
Q12.(i)It is a safety device to protect an electric circuit from overloading or short circuiting. It is a piece of wire of a material of low melting point which is connected to the live wire in the circuit. ... When an excessive current flows, the fuse melts and the circuit is broken.
(ii)The heater's heating element is made up of an alloy that has very high resistance, so when current flows through the heating element, it becomes too hot and glows red. But the cord's resistance, which is usually of copper or aluminium, is low, so it does not glow.
Q13.construction
An AC generation is an electric generation that converts mechanical energy
into electrical energy in form of alternative emf or alternating current it works as the principals of Electromagnetic Inductor
working of an generator: Whne the armature rotate between the poles of the magnet an axis perpendicular to the magnetic field the flux which links with the armature changes continuously Due to this on emf is induced in the armature This produces on electric current through galvanometer & the slip rings & brushes.
The galvanometer rings between the positive & negative values This indicates that there's is an alternating current flowing through the galvanometer.
Explanation:
hope this will help you dear
please mark as brainlist
Answer:
Explanation:
Q8 campare the following
(a) sorry i dont khon the answer of this ques
(b)12 Ohm and 2 Ohm resistors are connected in parallel. The voltage across each component of a parallel circuit remains the same. Hence, the voltage across 2 Ohm resistor will be 4 V. Therefore, the power used by 2 Ohm resistor is 8 W.
Q9 diagram in above
Q10.explain:
A convex lens can be regarded as made of a very large number of portions of triangular prisms. The bases of these prisms are towards the central thicker portion of the lens.
(2) A ray of light passing through a prism bends towards its base. Hence, a convex lens converges the rays falling on it.
Q11.The actual solar cells are made of silicon semiconductors that absorb sunlight and then convert it into electricity. Currently, solar panels that are used for domestic purposes are only able to take around 20% of the sunlight that they receive and turn it into electricity. This is what is known as solar efficiency.
Q12.(i)It is a safety device to protect an electric circuit from overloading or short circuiting. It is a piece of wire of a material of low melting point which is connected to the live wire in the circuit. ... When an excessive current flows, the fuse melts and the circuit is broken.
(ii)The heater's heating element is made up of an alloy that has very high resistance, so when current flows through the heating element, it becomes too hot and glows red. But the cord's resistance, which is usually of copper or aluminium, is low, so it does not glow.
Q13.construction
An AC generation is an electric generation that converts mechanical energy
into electrical energy in form of alternative emf or alternating current it works as the principals of Electromagnetic Inductor
working of an generator: Whne the armature rotate between the poles of the magnet an axis perpendicular to the magnetic field the flux which links with the armature changes continuously Due to this on emf is induced in the armature This produces on electric current through galvanometer & the slip rings & brushes.
The galvanometer rings between the positive & negative values This indicates that there's is an alternating current flowing through the galvanometer.
Explanation:
hope this will help you dear
please mark as brainlist