English Medium कक्षा १० - CBSE Question Bank Solutions

Oxidation is a process which involves ____________.

The process of reduction involves ____________.

\[\ce{MnO2 + 4HCl -> + 2H2O + Cl2}\]

Identify the substance oxidized in the above equation.

When Ag is exposed to air it gets a black coating of ____________.

Select the oxidising agent for the following reaction:

\[\ce{H2S + I2 -> 2HI + S}\]

In the reaction of iron with copper sulphate solution:

CuSO₄ + Fe → Cu + FeSO₄

Which option in the given table correctly represents the substance oxidized and the reducing agent?

Two wires of the same length and area made of two materials of resistivity ρ₁ and ρ₂ are connected in series to a source of potential V. The equivalent resistivity for the same area is:

If R₁ and R₂ be the resistance of the filament of 40 W and 60 W respectively operating 220 V, then:

The resistance of the hot filament of the bulb is about 10 times the cold resistance. What will be the resistance of 100 W-220 V lamps, when not in use?

What is the maximum resistance which can be made using five resistors each of `1/5` W?

If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be:

In an electrical circuit, two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be ______.

The north pole of Earth’s magnet is in the ____________.

A current-carrying conductor is held in an exactly vertical direction. In order to produce a clockwise magnetic field around the conductor, the current should be passed in the conductor:

When a 4 Ω resistor is connected across the terminals of a 2 V battery, the number of coulombs passing through the resistor per second is:

The shape of the magnetic field lines produced by a current-carrying conductor is ____________.

Two electric bulbs have resistances in the ratio 1 : 2. If they are joined in series, the energy consumed in them is in the ratio:

A current flows in a wire running between the S and N poles of a magnet lying horizontally as shown in the figure below:

The force on the wire due to the magnet is directed ____________.

The strength of magnetic field around a current-carrying conductor is ____________.

When current is parallel to a magnetic field, then force experience by the current-carrying conductor placed in a uniform magnetic field is ____________.