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SAI INTERNATIONAL SCHOOL
PHYSICS
CLASS X
Chapter: ELECTRICITY
Objective Questions:

1.An electrical appliance has a resistance of 25 Ω. When this electrical appliance is
connected to a 230 V supply line, the current passing through it will be:

A. 9.2 A

B. 92 A

C. O.92 A

D.2.9 A

2. SI unit of resistance

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A. Ohm m B. Ohm m C. Ohm D. Volt ampere
3. Resistivity of a material depends on its

A. length B. Area of cross section C. Nature D. All of these

Subjective questions:

4.If the resistance of an electric iron is 50Ω and 3.2A Current flows through the
resistance. Find the voltage between two points.

5.An EMF source of 8.0 V is connected to a light bulb. An electric current of 2.0 A
flows through it. Calculate the resistance offered by the electrical appliance.

6.If the filament resistance of an electric bulb is 330 Ω and Potential difference of two
points 110V. Find the current flowing through the filament.

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7.A wire of length 3 m and area of cross-section 1.7 × 10 m has a resistance 3 ×
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10 ohm.
a. What is the formula for resistivity of the wire and what is the unit of it
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b. Calculate the resistivity of the wire Ans:ρ=1.7×10 Ohm-m

8.On what factors does the resistance of a conductor depend?
B. Will current flow more easily through a thick wire or a thin wire of the same
material, when connected to the same source? Why?
Pre-Activity Questions:

State ohm’s law.

Define the constant obtained from it.