{"id":1826,"date":"2020-08-27T18:54:36","date_gmt":"2020-08-27T18:54:36","guid":{"rendered":"https:\/\/murreeroad.org\/physics10\/?p=1826"},"modified":"2020-10-18T23:15:06","modified_gmt":"2020-10-18T18:15:06","slug":"current-electricity","status":"publish","type":"post","link":"https:\/\/murreeroad.org\/physics10\/current-electricity\/","title":{"rendered":"Current Electricity"},"content":{"rendered":"

Unit 14 Current Electricity\u00a0(Short Questions)<\/strong><\/h2>\n

Q.1 What is electric current? Write its formula to calculate it. <\/a><\/strong><\/p>\n

Q.2 Write the two smaller units of current. <\/a><\/strong><\/p>\n

Q.3 What is difference between Galvanometer and Ammeter?<\/a><\/strong><\/p>\n

Q.4 What is the difference between cell and battery?<\/a><\/strong><\/p>\n

Q.5 In order to measure current in a circuit; why ammeter. is always connected in series?\u00a0<\/a><\/strong><\/p>\n

Q.6 Define Volt.\u00a0<\/a><\/strong><\/p>\n

Q.7\u00a0<\/strong>Define Electro Motive Force. Write its S.l Unit.<\/strong><\/a><\/p>\n

Q.8 <\/strong>What is digital multimeter?\u00a0<\/strong><\/a><\/p>\n

Q.9 How we measure e.m.f of a battery?\u00a0<\/a><\/strong><\/p>\n

Q.10 Define Ohm. Write its symbol.\u00a0<\/a><\/strong><\/p>\n

Q.11 What do you mean by Ohmic and Non-Ohmic conductors?<\/a><\/strong><\/p>\n

Q.12 Diamond does not conduct electricity however it is very good at conducting heat, explain.\u00a0<\/a><\/strong><\/p>\n

Q.13 How do the Jewelers identify diamonds as real or a fake one?<\/a><\/strong><\/p>\n

Q.14 Write an example of use of heating effect of current.\u00a0<\/a><\/strong><\/p>\n

Q.15 Which metal is used as the filament of an electric bulb? Explain.<\/a><\/strong><\/p>\n

Q.16 Define Insulator. Give one example.<\/a><\/strong><\/p>\n

Q.17 How many methods of combination of resistors?<\/a><\/strong><\/p>\n

Q.18 What is meant by equivalent resistance of series circuit?<\/a><\/strong><\/p>\n

Q.19 Write down two advantages of Parallel Circuit of Resistors.<\/a><\/strong><\/p>\n

Q.20 Define Joule’s law. Write its equation.<\/a><\/strong><\/p>\n

Q.21 Define Kilo watt Hour and Write equation of quantity of energy in kilowatt hour.\u00a0<\/a><\/b><\/p>\n

Q.22 Write down formula to calculate the value of electricity bill.<\/a><\/strong><\/p>\n

Q.23 Differentiate between D.C and A.C.<\/a><\/strong><\/p>\n

Q.24 Describe two reasons of cable’s insulation damage.\u00a0<\/a><\/strong><\/p>\n

Q.25 Write the two methods of safe use of electricity in houses.<\/a><\/strong><\/p>\n

Q.26 Differentiate between Live and Neutral Wire.<\/a><\/strong><\/p>\n

Q.27 What is difference between fuse and circuit breaker?\u00a0<\/a><\/strong><\/p>\n

Q.28 Does a fuse in a circuit control the potential difference or the current?\u00a0<\/a><\/strong><\/p>\n

Q.29 What is meant by circuit breaker?\u00a0<\/a><\/strong><\/p>\n

Q.30 Describe two advantages of earth wire in electric circuit.<\/a><\/strong><\/p>\n

Q.31 How does the earth wire save us from electric shock when the livewire of the electric appliances gets damaged?\u00a0<\/a><\/strong><\/p>\n

Q.32 What is difference between current flow and water flow?\u00a0<\/a><\/strong><\/p>\n

Q.33 Define conventional current.\u00a0<\/a><\/strong><\/p>\n

Q.34 Write briefly the function of galvanometer.\u00a0<\/a><\/strong><\/p>\n

Q.35 In order to measure, current in a circuit, why ammeter is always connected in series?\u00a0<\/a><\/strong><\/p>\n

Q.36 Which device is used to measure the current in circuit? How it is connected?\u00a0<\/a><\/strong><\/p>\n

Q.37 What is meant by Potential difference?<\/a><\/strong><\/p>\n

Q.38 When and who invented first practical battery?\u00a0<\/a><\/strong><\/p>\n

Q.39 Which are sources of emf? Write names.<\/a><\/strong><\/p>\n

Q.40 State Ohm’s law and write its equation.<\/a><\/strong><\/p>\n

Q.41 What are the limitations on the Ohm’s Law?\u00a0<\/a><\/strong><\/p>\n

Q.42 Define Resistance.\u00a0<\/a><\/strong><\/p>\n

Q.43 What is meant by Thermistor?\u00a0<\/a><\/strong><\/p>\n

Q.44 Define specific resistance.\u00a0<\/a><\/strong><\/p>\n

Q.45 Why does the Resistance of conductor increases with the increase in temperature?\u00a0<\/a><\/strong><\/p>\n

Q. 46 Define conductor and give two examples.\u00a0<\/a><\/strong><\/p>\n

Q.47 State the difference between Conductors and Insulators.<\/a><\/strong><\/p>\n

Q.48 Describe two features of series combination of resistors.\u00a0<\/a><\/strong><\/p>\n

Q.49 Write down two features of parallel combination of resistance.<\/a><\/strong><\/p>\n

Q.50 Define Electric Power and also write formula to find it.<\/a><\/strong><\/p>\n

Q.51 What is the unit of electric power? Define it.<\/a><\/strong><\/p>\n

Q.52 Define watt.<\/a><\/strong><\/p>\n

Q.53. Define kilowatt-Hour.<\/a><\/strong><\/p>\n

Q.54 Describe two major hazards of Electricity.<\/a><\/strong><\/p>\n

Q.55 What are damp conditions?<\/a><\/strong><\/p>\n

Q.56 Describe two causes of short circuiting.<\/a><\/strong><\/p>\n

Q.57 What is fuse? Write down its different ranges.<\/a><\/strong><\/p>\n

<\/a>Q.1 What is electric current? Write its formula to calculate it. <\/strong><\/p>\n

Ans: Electric Current: The rate of flow of electric charge through any cross sectional area is called current.<\/p>\n

Formula: If the charge Q is passing through any area ill time t, then current I flowing through it will be given by<\/p>\n

Current = Charge \/ Time<\/p>\n

I = Q \/ t<\/p>\n

Unit: SI unit of current is ampere (A).<\/a><\/p>\n

Q.2 Write the two smaller units of current. <\/strong><\/p>\n

Ans: Ampere: An ampere is a unit of current. If a charge of one coulomb passes through a cross-sectional area in one second then current is one ampere. Smaller units of current are milli ampere (mA) micro ampere\u00a0 (\u03bcA). <\/em>Which are defined below as;<\/p>\n

1 mA = 10-3<\/sup> A<\/p>\n

1 \u03bc<\/em>A\u00a0 = 10-6<\/sup> A<\/a><\/p>\n

Q.3 What is difference between Galvanometer and Ammeter?<\/strong><\/p>\n

Ans: Galvanometer:<\/strong> Galvanometer is a sensitive instrument and can detect small current in a circuit. It is connected in series, so the current flowing in the circuit also passes through the galvanometer.<\/p>\n

Ammeter:<\/strong> A large current of the range such as 1 A or 10 A can be measured by means of ammeter.Ammeter is connected in series, so the current flowing in the circuit also passes through the ammeter.<\/a><\/p>\n

Q.4 What is the difference between cell and battery?<\/strong><\/p>\n

Ans: Cell:<\/strong> A cell is single unit at the base voltage.<\/p>\n

Battery:<\/strong> A battery can be single cell or multiple cells connected together in series or parallel to make the voltage current rating as required.<\/a><\/p>\n

Q.5 In order to measure current in a circuit; why ammeter. is always connected in series?\u00a0<\/strong><\/p>\n

Ans: Like galvanometer, ammeter is also connected in series, so the current flowing in the circuit also passes through the ammeter.<\/a><\/p>\n

Q.6 Define Volt.\u00a0<\/strong><\/p>\n

Ans: Volt:<\/strong> The potential difference between two point will be I volt if 1 J of energy consumed by I c charge while flowing between two point.<\/p>\n

Formula:\u00a0 1 V = 1 JC-1<\/a><\/sup><\/p>\n

Q.7 Define Electro Motive Force. Write its S.l Unit.<\/strong><\/p>\n

Ans: Electromotive Force (e.m.f):\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0<\/strong><\/p>\n

The energy converted from ~o’n-electrical forms to electrical form when one coulomb of positive charge passes through the battery.<\/p>\n

Formula:<\/strong> e.m.f = Energy \/ Charge<\/p>\n

E = w \/ Q<\/p>\n

Unit:<\/strong> The unit of e.m.f is JC-1<\/sup><\/p>\n

In SI system JC-1<\/sup> is equal to one volt ( 1 V )<\/a><\/p>\n

Q.8 What is digital multimeter?\u00a0<\/strong><\/p>\n

Ans: A\u00a0digital multimeter<\/b>\u00a0is a test tool used to measure two or more electrical values\u2014principally voltage (volts), current (amps) and resistance (ohms). It is a standard diagnostic tool for technicians in the electrical\/electronic industries.<\/a><\/p>\n

Q.9 How we measure e.m.f of a battery?\u00a0<\/strong><\/p>\n

Ans: In order to measure e.m.f of the battery we connect voltmeter-directly with the terminal of the battery.<\/a><\/p>\n

Q.10 Define Ohm. Write its symbol.\u00a0<\/strong><\/p>\n

Ans: Ohm:<\/strong> When a potential difference of one volt is applied across the ends of a conductor and one ampere of current passes’ through it, thus its resistance will be one ohm.<\/p>\n

Symbol:<\/strong> It is represented by \u03a9<\/a><\/p>\n

Q.11<\/strong> What do you mean by Ohmic and Non-Ohmic conductors?<\/strong><\/p>\n

Ans: Ohmic Conductors:\u00a0<\/strong><\/p>\n

Materials that obey Ohm’s law, and hence have a constant resistance over a wide range of voltages, are said to be Ohmic.<\/p>\n

Examples:<\/strong> most metals show ohmic behaviour.<\/p>\n

Non-Ohmic Conductors:<\/strong><\/p>\n

Materials having resistance those changes with Voltage or current are non-ohmic.<\/p>\n

Examples:<\/strong> Thermistor and filament are non-ohmic.<\/a><\/p>\n

Q.12 Diamond does not conduct electricity however it is very good at conducting heat, explain.\u00a0<\/strong><\/p>\n

Ans: Diamond does not conduct electricity because it has no free electrons. However, it is very good at conducting heat because its particles are. very firmly bonded together.<\/a><\/p>\n

Q.13 How do the Jewelers identify diamonds as real or a fake one?<\/strong><\/p>\n

Ans: Jewelers identify diamonds as real or a fake one made from glass, by holding it to their lips. A real diamond ability of transferring heat four or gives time better then copper.<\/a><\/p>\n

Q.14 Write an example of use of heating effect of current. \u00a0<\/strong><\/p>\n

Ans: We use heating effect of an electric current for different purposes. When a current flows through the filament of bulb it glows white hot and give out light. Electric heaters have very thin wires that glow red hot when current flows.<\/a><\/p>\n

Q.15 Which metal is used as the filament of an electric bulb? Explain.<\/strong><\/p>\n

Ans: Tungsten filament is used in electric bulb. Because tungsten has the highest melting point of all metals and it does not melt even when it is\u00a0glowing.<\/a><\/p>\n

Q.16 Define Insulator. Give one example.<\/strong><\/p>\n

\u00a0<\/strong>Ans: Insulator Material:\u00a0<\/strong><\/p>\n

The substances through which electric current cannot flow are called insulators.<\/p>\n

Examples:<\/strong> Examples of insulator are:<\/p>\n

i.\u00a0 \u00a0Rubber \u00a0\u00a0\u00a0\u00a0\u00a0 ii. \u00a0\u00a0\u00a0\u00a0 Glass \u00a0\u00a0\u00a0\u00a0\u00a0 iii.\u00a0 \u00a0 \u00a0Plastic\u00a0 \u00a0 \u00a0 \u00a0 \u00a0iv. Wood\u00a0 \u00a0 \u00a0 \u00a0 v.\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Silk<\/a><\/p>\n

Q.17 How many methods of combination of resistors?<\/strong><\/p>\n

Ans: Resistors can be connected in two ways.<\/p>\n

(i) \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Series combination \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 (ii) \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Parallel combination<\/a><\/p>\n

Q.18 What is meant by equivalent resistance of series circuit?<\/strong><\/p>\n

Ans: Formula is given by:<\/p>\n

Rc<\/sub> = R1<\/sub> + R2<\/sub> + R3<\/sub> + ……. + Rn<\/sub>
\nWhere R1<\/sub> and R3<\/sub> are R connected in series.<\/a><\/p>\n

Q.19 Write down two advantages of Parallel Circuit of Resistors.<\/strong><\/p>\n

Ans: Two advantages of parallel circuit of resistors:<\/p>\n

i) Each device in the circuit receives the full battery volt<\/p>\n

ii) Each device in the circuit may be turned off independently without stopping the current flowing to the other devices in the circuit, This principle is used in household wiring.<\/a><\/p>\n

Q.20 Define Joule’s law. Write its equation.<\/strong><\/p>\n

Ans: Joule’s law:<\/strong><\/p>\n

The amount of heat generated in a resistance due to flow of charges is equal to the product of square of current I, resistance R and the time duration t.<\/p>\n

\u00a0 Formula:<\/strong> \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 W = I2<\/sup>Rt<\/p>\n

W = V2<\/sup>t \/ R<\/a><\/p>\n

Q.21 Define Killowatt Hour and Write equation of quantity of energy in kilowatt hour.\u00a0<\/strong><\/p>\n

Ans: Kilowatt Hour:<\/strong><\/p>\n

The amount of energy delivered by a power of one kilowatt in -one hour is called kilowatt-hour.<\/p>\n

Formula:<\/strong> amount of energy in kwh = watt x time is use in hour<\/u>\u00a0 \/ 1000<\/a><\/p>\n

Q.22 Write down formula to calculate the value of electricity bill.<\/strong><\/p>\n

Ans: Cost of electricity = number of unit consumed x cost of one unit.<\/p>\n

Watt x time of use in hours \/ 1000 x cost of new unit.<\/a><\/p>\n

Q.23 Differentiate between D.C and A.C.<\/strong><\/p>\n

Ans: In\u00a0direct current<\/b>\u00a0(DC<\/b>), the electric charge (current) only flows in one direction.<\/p>\n

Alternating Current<\/strong> (AC<\/b>), on the other hand, changes direction periodically. The voltage in\u00a0AC<\/b>\u00a0circuits also periodically reverses because the current changes direction.<\/a><\/p>\n

Q.24 Describe two reasons of cable’s insulation damage.\u00a0<\/strong><\/p>\n

Ans: Two reasons of cables insulation damage is:<\/p>\n

    \n
  1. i) too much moisture ii) \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 constant friction.<\/a><\/li>\n<\/ol>\n

    Q.25 Write the two methods of safe use of electricity in houses.<\/strong><\/p>\n

    Ans:\u00a0 1. Fuses should be connected in the livewire so that the appliance will not operate after the fuse has blown.<\/p>\n

    2.\u00a0 Switch OFF the main before changing any fuse.<\/a><\/p>\n

    Q.26 Differentiate between Live and Neutral Wire.<\/strong><\/p>\n

    Ans: Live Wire:<\/strong> Live wire is a high potential wire which has the potential 220 V.
    \nNeutral Wire:<\/strong> Neutral wire is a wire which has 0 V potential and it provides the return path for the current.    <\/a><\/p>\n

    Q.27 What is difference between fuse and circuit breaker?\u00a0<\/strong><\/p>\n

    Ans: Fuse:<\/strong> A fuse is a safety device’ that is connected in series with the live’ wire in the circuit to protect the equipment’s when excess current flows.
    \nCircuit Breaker:<\/strong> The circuit breaker, acts as a safety device in the same way as a fuse. It disconnects the .supply automatically, if current exceeds the normal value.    <\/a><\/p>\n

    Q.28 Does a fuse in a circuit control the potential difference or the current?\u00a0<\/strong><\/p>\n

    Ans: In electric circuit fuse control the current.<\/a><\/p>\n

    Q.29 What is meant by circuit breaker?\u00a0<\/strong><\/p>\n

    Ans: Circuit Breaker:<\/strong> The circuit breaker acts as a safety device in the same way as a fuse. It disconnects the supply automatically if current exceed the normal value.<\/a><\/p>\n

    Q.30 Describe two advantages of earth wire in electric circuit.<\/strong><\/p>\n

    Ans: i) We will get an electric shock if the livewire inside an appliance comes loose and touches the metal easing. However, the earth terminal is connected. to the metal casing, so the current goes through the Earth wire instead of passing through our body arid casing an electric shock.<\/p>\n

    ii) A strong current passes through the Earth wire because it has a, very low resistance. This breaks the fuse and disconnects the appliance. <\/a>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 .<\/p>\n

    Q.31 How does the earth wire save us from electric shock when the livewire of the electric appliances gets damaged?\u00a0<\/strong><\/p>\n

    Ans: We will get an electric shock if the live wire inside an appliance comes loose and touches the metal casing. However,’ the earth terminal is connected to the metal casing, so the current goes through the Earth wire instead of passing through our body and causing an electric shock.<\/a><\/p>\n

    Q.32 What is difference between current flow and water flow?\u00a0<\/strong><\/p>\n

    Ans: The flow of charge in a circuit is like the flow of water in a pipe except that a conducting wire is needed in order to have a complete conducting path.<\/a><\/p>\n

    Q.33 Define conventional current.\u00a0<\/strong><\/p>\n

    Ans: Conventional Current:<\/strong> The electric current due to flow of positive charge carries is-called conventional current.<\/p>\n

    Direction:<\/strong> Its direction is always from positive terminal to the battery to the negative terminal of the battery.<\/a><\/p>\n

    Q.34 Write briefly the function of galvanometer.\u00a0<\/strong><\/p>\n

    Ans: Galvanometer:<\/strong> Galvanometer is very sensitive instrument and can detect small current in a circuit. A current of few milli amperes is sufficient to cause full scale deflection in it. Of the connection polarity should keep in mind while use galvanometer. After suitable modification galvanometer can be converted into an ammeter.<\/a><\/p>\n

    Q.35 In order to measure, current in a circuit, why ammeter is always connected in series?\u00a0<\/strong><\/p>\n

    Ans: Like galvanometer, ammeter is also connected in series, so the current flowing in the circuit also passes through the ammeter.<\/a><\/p>\n

    Q.36 Which device is used to measure the current in circuit? How it is connected?\u00a0<\/strong><\/p>\n

    Ans: Am-meter is used for measurement of electric current. It always connected in series while measuring electric current.<\/a><\/p>\n

    Q.37 What is meant by Potential difference?<\/strong><\/p>\n

    Ans: The work done by carrying a unit positive charge from point A to B against electric field is called potential difference.<\/p>\n

    Unit:<\/strong> SI unit of potential difference is volt.<\/p>\n

    Formula:<\/strong> Potential difference can be determined from the following\u00a0 V = W \/ q<\/a><\/p>\n

    Q.38 When and who invented first practical battery?\u00a0<\/strong><\/p>\n

    Ans: The volt is named after the Italian physicist Alessandro Volta (1745 – 1827). Who developed the first practical electric battery in 1800, known as a voltaic pile.<\/a><\/p>\n

    Q.39 Which are sources of emf? Write names.<\/strong><\/p>\n

    Ans: Battery, dry cells etc are sources of emf.<\/a><\/p>\n

    Q.40 State Ohm’s law and write its equation.<\/strong><\/p>\n

    Ans: Ohm’s Law:<\/strong>
    \nThe amount of current passing through a conductor is directly proportional to the potential difference applied across its ends, provided the temperature and the physical state of the conductor do not change.<\/p>\n

    Equation<\/strong>\u00a0 \u00a0 \u00a0I \u221d V<\/p>\n

    V \u221d I<\/p>\n

    V = IR<\/a><\/p>\n

    Q.41 What are the limitations on the Ohm’s Law?\u00a0<\/strong><\/p>\n

    Ans: Condition of Ohm’s law:<\/strong><\/p>\n

    i. Ohm’s law is valid only for metals (specific metals).<\/p>\n

    ii. Ohm’s law is valid if the temperature and the physical state ‘of metals do not change.<\/a><\/p>\n

    Q.42 Define Resistance.\u00a0<\/strong><\/p>\n

    Ans: Resistance:<\/strong> The property of a substance which offers opposition to the flow of current through it is called its resistance.<\/p>\n

    Unit:<\/strong> Its S.I unit is Ohm (\u03a9).<\/a><\/p>\n

    Q.43 What is meant by Thermistor?\u00a0<\/strong><\/p>\n

    Ans: A type of electrical resistor whose resistance is greatly reduced by heating used for measurement and control. Its resistance decreases when temperature increases.<\/a><\/p>\n

    Q.44 Define specific resistance.\u00a0<\/strong><\/p>\n

    Ans: Specific Resistance:<\/strong> The resistance of conductor of one meter cube is called resistivity.<\/p>\n

    Formula:\u00a0 \u00a0<\/strong>R =\u00a0 \u03c1 L \/ A<\/p>\n

    If we put L = 1 m and A= 1 m2<\/sup> in above equation, then R = p, “The resistance of, one meter, cube of a substance is equal to its specific resistance.”<\/p>\n

    Unit:<\/strong> The unit of “\u03c1” is ohm-meter (\u03a9m).<\/a><\/p>\n

    Q.45 Why does the Resistance of conductor increases with the increase in temperature?\u00a0<\/strong><\/p>\n

    Ans: The resistance of conductors increases with increase in temperature. This is due to increase in the number of collisions of electrons with themselves and with the atoms of the metals.<\/a><\/p>\n

    Q. 46 Define conductor and give two examples.\u00a0<\/strong><\/p>\n

    Ans: Conductor:<\/strong> The substance which allow electric current to pass through them are called conductors.<\/p>\n

    Examples:<\/strong> Metals like iron, copper and silver etc. are examples of conductors.<\/a><\/p>\n

    Q.47 State the difference between Conductors and Insulators.<\/strong><\/p>\n

    Ans: Conductors:<\/strong>
    \nSuch materials which show less resistance to the flow of current are called conductors, for example iron copper etc.<\/p>\n

    Insulators:<\/strong> Such materials which have very large value of resistance to the flow of current are called insulators i.e., rubber, glass, plastic etc.<\/a><\/p>\n

    Q.48 Describe two features of series combination of resistors.\u00a0<\/strong><\/p>\n

    Ans: Features of series combination of resistors:<\/strong><\/p>\n

    In series combination resistors are connected end to end and electric current has a single path through the circuit.<\/p>\n

    Following are the features of series combination of resistors:<\/p>\n

    i. In series combination the current passing through each resistor is the same.
    \nii. The potential difference of each resistors will be different.    <\/a><\/p>\n

    Q.49 Write down two features of parallel combination of resistance.<\/strong><\/p>\n

    Ans: Features of parallel combination of resistance:<\/p>\n

      \n
    1. The sum of currents in all the resistors is equal to the current supplied by the battery in parallel combination of resistors. I = I1<\/sub> + I2<\/sub> + I3<\/sub> + …<\/li>\n
    2. The voltage across each resistance in parallel potential difference is same.<\/a><\/li>\n<\/ol>\n

      Q.50 <\/strong>Define Electric Power and also write formula to find it.<\/p>\n

      Ans: Electric Power: <\/strong>The amount of energy supplied by current in unit time is known as electric power.<\/p>\n

      Formula:<\/strong> \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 P = QV \/ t<\/p>\n

      = IV<\/p>\n

      = I2<\/sup>R<\/p>\n

      Unit:<\/strong> The unit of power is watt (W).
      \nDefinition of Unit of Electric Power:<\/p>\n

      The unit of electric power is watt which is equal to one Joule per second ( I Js-1<\/sup> ).<\/a><\/p>\n

      Q.51 What is the unit of electric power? Define it.<\/strong><\/p>\n

      Ans: Electric Power:<\/strong><\/p>\n

      The amount of energy supplied by current in unit time is known as electric power.<\/p>\n

      Watt:<\/strong> The unit of electric power is watt (w).<\/p>\n

      Watt = Joule \/ second<\/p>\n

      W\u00a0 \u00a0=\u00a0 J \/ s<\/p>\n

      One watt is a power if on joule energy used in one second.<\/a><\/p>\n

      Q.52 Define watt.<\/strong><\/p>\n

      Ans: One watt is a power if one Joule energy used in one second. Watt is denoted by W.<\/a><\/p>\n

      Q.53. Define kilowatt-Hour.<\/strong><\/p>\n

      Ans: Kilowatt-Hour: <\/strong>The amount of energy delivered by a power of one kilowatt in one hour is called kilowatt-hour. Kilowatt-hour is denoted by kWh.<\/a><\/p>\n

      Q.54 Describe two major hazards of Electricity.<\/strong><\/p>\n

      Ans: i. Electric shock which cause human death<\/p>\n

      ii. Fire due to short circuit.<\/a><\/p>\n

      Q.55 What are damp conditions?<\/strong><\/p>\n

      Ans: Damp Conditions:<\/strong> Such environment in which human resistance-become very low that conditions called damp conditions.<\/a><\/p>\n

      Q.56 Describe two causes of short circuiting.<\/strong><\/p>\n

      Ans: i. Melt wiring’s insulation.<\/p>\n

      ii. When live wire and neutral wires come in direct contact.<\/a><\/p>\n

      Q.57 What is fuse? Write down its different ranges.<\/strong><\/p>\n

      Ans: Fuse <\/strong><\/p>\n

      A fuse is a safety device.<\/p>\n

      Usage of fuse:<\/strong><\/p>\n

      Fuse is connected in series with the live wire in the circuit to protect the equipment’s when excess current flows. It is short and thin piece of metal wire that melts when large current passes through it. If a large, unsafe current passes through the circuit, the fuse melts and breaks the circuit before the wires become very hot and cause fire.<\/p>\n

      Range of fuse:<\/strong>\u00a0 Fuses are normally rated as’ 5A, 10A, 13A, 30A, etc.<\/p>\n

       <\/p>\n

       <\/p>\n","protected":false},"excerpt":{"rendered":"

      Unit 14 Current Electricity\u00a0(Short Questions) Q.1 What is electric current? Write its formula to calculate it. Q.2 Write the two smaller units of current. Q.3 What is difference between Galvanometer and Ammeter? Q.4 What is the difference between cell and battery? Q.5 In order to measure current in a circuit; why ammeter. is always connected… Read More »Current Electricity<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"off","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":""},"categories":[9],"tags":[],"_links":{"self":[{"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/posts\/1826"}],"collection":[{"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/comments?post=1826"}],"version-history":[{"count":17,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/posts\/1826\/revisions"}],"predecessor-version":[{"id":2031,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/posts\/1826\/revisions\/2031"}],"wp:attachment":[{"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/media?parent=1826"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/categories?post=1826"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/murreeroad.org\/physics10\/wp-json\/wp\/v2\/tags?post=1826"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}