English Medium कक्षा १० - CBSE Important Questions

Why should an ammeter have low resistance?

Two V-I graphs A and B for series and parallel combinations of two resistors are as shown. Giving reason state which graph shows (a) series, (b) parallel combination of the resistors.

A piece of wire of resistance R is cut into three equal parts. These parts are then connected in parallel. If the equivalent resistance of this parallel combination is R₁, what is the value of the ratio R₁ : R?

State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.

Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?

She wrote: Three-pin connections reduce heating of connecting wires.

1. Is her answer correct or incorrect? Justify.
2. What is the function of a fuse in a domestic circuit?

Vinita and Ahmed demonstrated a circuit that operates the two headlights and the two sidelights of a car, in their school exhibition. Based on their demonstrated circuit, answer the following questions.

1. State what happens when switch A is connected to:
   a) Position 2
   b) Position 3
2. Find the potential difference across each lamp when lit.
3. Calculate the current.
   a) in each 12 Ω lamp when lit.
   b) In each 4 Ω lamp when lit.
   OR
4. Show, with calculations, which type of lamp, 4.0 Ω or 12 Ω, has the higher power.

Consider the following combinations of resistors:

1. 
   
2. 
   
3. 
   
4. 
   
   The combinations having equivalent resistance 1 Q is/are ______.

An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.

How is Joule's law effect useful in electric circuits where fuse is used as a safety device?

Study the following circuit:

On the basis of this circuit, answer the following questions:

i. Find the value of total resistance between the points A and B.

ii. Find the resistance between the points B and C.

iii. Calculate the current drawn from the battery, when the key is closed

OR

iii. In the above circuit, the 16Ω resistor or the parallel combination of two resistors of 8 Ω, which one of the two will have more potential difference across its two ends? Justify your answer.

Which one of the following political parties came to power in Bolivia in 2006?

(A) The Communist Party

(B) The Republican Party

(C) The Socialist Party

(D) The Conservative Party

Why should the use of cattle cake as fuel be discouraged?

Why is the 'least cost' known as decision making factor for ideal location of an industry?

"Democracy is more effective than its other alternatives." Justify the statement.

What are Self Help Groups? How do they work? Explain.

In what respects is the criterion used by the UNDP for measuring development different from the one used by the World Bank?

How is community government elected in Belgium? 

What may be a developmental goal of a girl who belongs to a rich urban family ? 

What may be a developmental goal of a rich farmer? 

“Resource planning is a complex process.” Justify the statement with arguments.