Ohm's Law

Q.

State Ohms law. How can it be verified experimentally? Does it hold good under all conditions?

Q.

Give $5$ differences between ohmic and non-ohmic conductors.

Q.

How do you explain the relationship between voltage and current?

Q.

State ohms law. Express it mathematically. Define SI unit of resistance.

Q. With the increase in temperature, the resistance of a pure metal ____.

1. increases

2. decreases

3. does not change

4. first increases and then decreases

Q.

Find the potential difference required to flow a current of 200 mA in a wire of resistance 20 ohm.

1. $4V$

2. $2V$

3. $1V$

4. $3V$

Q. State and explain Ohm's law. How do you define 1 ohm?

Q.

A current 0. 2 A flows in a wire of resistance 15 $\Omega$. Find the potential difference across the ends of the wire.

Q.

Explain the principle of a potentiometer.

Q.

Ohm's law is applicable when physical conditions such as temperature is kept constant.

1. True

2. False

Q.

V-I graph of which material shows the straight line?

1. Gallium

2. Germanium

3. Silver

4. Silicon

Q.

Can we use copper wire instead of nichrome in the meter bridge?

Q.

Ohm’s Law gives the relation between potential difference and current.

1. True

2. False

Q.

The potential difference required to pass a current of 0.2 A through a wire of resistance 20 $\Omega$ is:

1. 4 V

2. 0.01 V

3. 40 V

4. 100 V

Q.

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

Q.

How are potential difference (V), current (I) and resistance (R) related?

1. V = I R

2. V I = R

3. I = V R

4. V = R / I

Q.

Power is said to be 1 kilowatt if 1000 J of work is being done per minute.

1. True
2. False

Q. Ohmic component have a V-I curve.

1. linear
2. parabolic
3. non-linear

Q. The current flowing through a resistor connected in an electric circuit and the potential difference developed across the ends of it are as shown in the diagram. Find the resistance of the resistor.

1. $0.024\Omega$
2. $17.5\Omega$
3. $0.057\Omega$
4. $24\Omega$

Q.

Three identical cells, each of $4\mathrm{V}$ and internal resistance $r$, are connected in series to a $6-\mathrm{ohm}$ resistor. If the current flowing in the circuit is $2\mathrm{A}$. The internal resistance of each cell is?

Q. The current flowing when a potential difference of $33V$ is applied across an appliance having a resistance of $110\Omega$ is $I$. If the same current $\left(I\right)$ is to flow through an appliance having a resistance of $500\Omega$, how much potential difference should be applied across it?

1. $220V$
2. $110V$
3. $250V$
4. $150V$

Q.

1. Name two bigger units of electric power and their relation with SI unit.

Q.

A cell of potential difference 12 V is connected to a bulb. The resistance of filament of bulb when it glows, is 24 $\Omega$. Find the current drawn from the cell.

Q.

Ohms law is valid________

Q.

State Ohms law. How can it be verified experimentally? Does it hold good under all conditions?

Q.

Which of the following also represent the electrical energy (VIT)?

1. $\frac{V^2}{R}$ $T^2$

2. None of these

3. $\frac{VIT}{R}$

4. $I^2$RT

Q. Ohm's law holds true at temperature and pressure.

1. constant
2. increasing
3. decreasing

Q.

The correct relation between Potential difference across the ends of the wire (V) and electric current through the wire (I) is:

1. H directly proportional to I

2. H directly proportional to (1/I²).

3. H directly proportional to (1/I)

4. H directly proportional to I²

Q. Question 14 (i)
Compare the power used in the $2\Omega$ resistor in each of the following circuits:
(i) a 6 V battery in series with $1\Omega$ and $2\Omega$ resistors.

Q. How do sensors work