English Medium Class 10 - CBSE Question Bank Solutions for Science

Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?

Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?

When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.

State the rule to determine the direction of a magnetic field produced around a straight conductor-carrying current.

State the rule to determine the direction of a current induced in a coil due to its rotation in a magnetic field.

Name one gustatory receptor and one olfactory receptor present in human beings.

Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form of heat, light and electricity

Name the unit of electrical resistance and give its symbol.

Name the physical quantity whose unit is "ohm".

When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Calculate the value of the resistance of the resistor.

 Name the law which is illustrated by the above V−I graph.

Ohm's law gives a relationship between:

(a) current and resistance
(b) resistance and potential difference
(c) potential difference and electric charge
(d) current and potential difference

The unit of electrical resistance is:

(a) ampere
(b) volt
(c) coulomb
(d) ohm

Keeping the p.d. constant, the resistance of a circuit is halved. The current will become:

(a) one-fourth
(b) four time
(c) half
(d) double

The graph between V and I for a conductor is a straight line passing through the origin. 

 Which law is illustrated by such a graph?

The graph between V and I for a conductor is a straight line passing through the origin. 

 What should remain constant in a statement of this law?

Fill in the following blank with suitable words: 

Resistance is measured in .............. The resistance of a wire increases as the length ..............; as the temperature ..............; and as the cross-sectional area .............. .

How should the two resistances of 2 ohms each be connected so as to produce an equivalent resistance of 1 ohm?

The resistors R₁, R₂, R₃ and R₄ in the figure given below are all equal in value. 

What would you expect the voltmeter A, B and C to read assuming that the connecting wires in the circuit have negligible resistance?

Four resistances of 16 ohms each are connected in parallel. Four such combinations are connected in series. What is the total resistance?