Question 3 :
A steady current passes through a wire of non-uniform cross-section. The quantities which depend on the Area of cross-section are:<br/>
Question 4 :
The current in a car headlamp is $3.0$A when connected to a $12$V battery. What is the resistance of the lamp when it is lit?
Question 5 :
Which of the following is an advantage of using electrical symbol?
Question 6 : You have the following appliances each of $500\ W$ running on  $220\ V$ a.c.: <div>(1) Electric iron.</div><div>(2) Electric lamp. </div><div>(3) Electric room heater. </div><div>The electric resistance is:</div>
Question 8 :
An electrical appliance has a resistance of 4 ohms. When it is connected to a 12 V battery, the number of coulombs passing through it per second is
Question 10 :
The heating element in an electric iron is made up of :
Question 12 :
The potential difference between the terminals of an electric heater is 220 V and the current is 5A. What is the resistance of the heater?
Question 14 :
Which of the following equipment does not work on principle of Joule's law?
Question 15 :
If $n$ is the number density of free electrons in a metallic wire, then the resistance is proportional to
Question 16 :
Which of the following will produce maximum wastage of electricity ?
Question 17 :
When potential difference is applied across an electrolyte, then Ohm's law is obeyed at
Question 18 :
Which pair is not correct for the instruments used in the laboratory and their uses from the following?
Question 20 :
Calculate the energy consumed by $2\ kW$ heater used for $1\ hr$ every day in a period of $30\ \text{days}$.
Question 21 :
If a $5 \,V$ battery is provoding $2 \,A$ current in a conductor then what is the resistance of conductor ?
Question 22 :
Which unit is not used in either the definition of the coulomb or the definition of the volt?<br>
Question 23 :
A table lamp of power $60 \ W$ consumed 9 (commerical) units of electricity in the month of April. For how many hours per day, on an average, was the lamp in use?
Question 24 :
If the electric potential difference between the two points is $V$ and resistance $R$, then the current between the points will be:
Question 25 :
Three heaters each rated $250 \ W$, $100 \ V$ are connected in parallel to a $100 \ V$ supply. The energy supplied in $kWh$ to the three heaters in $5 \ hours$ is :
Question 26 :
The energy expended in $1\  kW$ electric heater in $30\ \text{seconds}$ will be:
Question 27 :
<span>When electric current passes through the filaments of a bulb, it starts emitting light due to:</span>
Question 28 :
Assertion : The resistance of an ideal voltmeter should be infinite.<br>Reason : The potential difference measured by a voltmeter across a resistor is always less than the actual potential difference across the resistor.<br>
Question 29 :
A straight conductor of uniform cross section carries a current i. Let S be the specific charge on an electron. The momentum of all the free electrons per unit length of the conductor due to their drift velocity only is<br>
Question 30 :
A metallic wire of resistance $20\Omega$ is stretched such that its length becomes three times. The new resistance of the wire will be<br>
Question 31 :
An electrical conductor has a resistance of $5.6k\Omega$. A potential difference (p.d.) of $9.0V$ is applied<br>across its ends.<br>How many electrons pass a point in the conductor in one minute?
Question 32 :
How much energy in kilowatt hour is consumed in operating ten 50 watt bulbs for 10 hours per day in a month (30 days).
Question 34 :
In $N, e, \tau$ and $m$ are representing electron density, charge, relaxation time and mass of an electron respectively, then the resistance of wire of length $l$ and cross-sectional area $A$ is given by
Question 35 : Match the following :<br/><table class="wysiwyg-table"><tbody><tr><td>List - I </td><td> List - II</td></tr><tr><td>a) Resistivity</td><td>e) volt</td></tr><tr><td>b) Conductivity</td><td>f) siemen</td></tr><tr><td>c) emf</td><td>g) ohm-metre</td></tr><tr><td>d) conductance</td><td>h) mho / metre</td></tr></tbody></table>
Question 36 :
Calculate the total power of $2$ fans, if each of them draws a current of $5\ A$ at a potential difference of $200\ V$.
Question 37 :
A solenoid is at potential of difference $60\ V$ and current flows through it is $15$ ampere, then the resistance of coil will be
Question 38 :
Which of these will consume most units of energy in a day?<br>
Question 40 :
A $1000 W$ heating unit is designed to operate on a $120 V$ line. If line voltage drops to $110 V$, then the percentage of heat output drops by:<br>
