10th Class Physics Chapter 5 Notes Urdu Medium

Complete Notes on Chapter No.14:  10th Class Physics Chapter 5 Notes Urdu Medium in Physics Urdu Medium written by Professor Sir Fahad Abbas Suib. These computerized notes are very helpful in the preparation of Current Electricity Class 10 Notes for students of the Physics and these are according to the paper patterns of all Punjab boards.

• Our comprehensive 10th Class Physics Chapter 5 Notes Urdu Medium will ensure you're fully prepared for your exams.
• The field of electrodynamics or current electricity deals with the study of electric charges in motion. The substances through which electric charges can flow very easily are called conductors (e.g. Gold, silver, copper, etc.) the substances through which Electric charges cannot flow are called Insulators. (e.g. rubber, wood, paper, dry air, etc).
• Charges in motion constitute electric current. This chapter will introduce you to current electricity and related phenomena such as conventional current, Ohm's law, electric power, Joule’s heating effect, hazards of electricity and safety measures. We will also learn how current or voltage is measured in a circuit by electrical devices.
• ELECTRIC CURRENT: Most of the electric charge around us is bound in neutral atoms. It is not easy to overcome the electrostatic force of attraction between the nuclei and electrons in an atom. However, in metals some electrons are not tightly bound to nuclei and are free to move around randomly. They have weak force between them and the nucleus.
• Similarly, in solutions some positive and negative charges can freely move around randomly. When such free charges are exposed to an external electric field, they move in a specific direction, and thus constitute current. Electric current is produced due to the flow of either positive charge or negative charge or both of charges at the same time.
• In metals, the current is produced only due to the flow of free electrons i.e., negative charges. In case of electrolyte its molecules in aqueous solution dissociate among positive and negative ions. So the current in electrolyte is produced due to the flow of both positive and negative charges.
• "The rate of flow of electric charge through any crosssectional area is called current".
• If the charge Q is passing through any area in time t, then current I flowing through it will be given by      Current = Charge / Time  or I = Q / t    SI unit of current is ampere (A).
• 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 (µA), which are defined below as:  1 mA = 10^-3 A,    1 µA = 10^-6 A.
• Define electric current.
• Describe the concept of conventional current. 
• Understand the potential difference across a circuit component and name its unit.
• Describe Ohm’s law and its limitations. • define resistance and its unit(Ω).
• Calculate the equivalent resistance of a n u mber of resistances connected in series and also in parallel.
• Describe the factors affecting the resistance of a metallic conductor.
• Distinguish between conductors and insulators.
• Sketch and interpret the V-I characteristics graph for a metallic conductor, a filament lamp and a thermister.
• Describe how energy is dissipated in a resistance and explain Joule’s law.
• Apply the equation     E = I,  Vt = I^2,     Rt = V^2 t /R to solve numerical problem.
• Calculate the cost of energy when given the cost per kWh.
• Distinguish between D.C and A.C.
• Identify circuit components such as switches, resistors, batteries etc.
• describe the use of electrical measuring devices like galvanometer, ammeter and voltmeter (construction and working principles not required).
• Construct simple series (single path) and parallel circuits (multiple paths).
• Predict the behaviour of light bulbs in series and parallel circuit such as for celebration lights.
• State the functions of the live, neutral and earthwires in the domestic main supply.
• State reason why domestic supplies are connected in parallel.
• Describe hazards of electricity (damage insulation, overheating of cables, damp conditions).
• Explain the use of safety measures in household electricity, (fuse, circuit breaker, earthwire).
• Calculate the total cost of electrical energy. Suggest ways how it can be reduced without compromising the comforts and benefits of electricity.