पदार्थों के चुंबकीय गुण Magnetic Properties of Materials Chapter 5 | Class 12 Physics | Gopal Sir

Class 12th Physics | Easy & Hard Most Important Chapters

Electrical resistance of certain materials, known as superconductors, changes abruptly from a nonzero value of zero as their temperature is lowered below a critical temperature T_(C) (0) . An interesting property of super conductors is that their critical temperature becomes smaller than T_(C) (0) if they are placed in a magnetic field, i.e., the critical temperature T_(C) (B) is a function of the magnetic field strength B. The dependence of T_(C) (B) on B is shown in the figure. . A superconductor has T_(C) (0) = 100 K . When a magnetic field of 7.5 Tesla is applied , its T_(C) decreases to 75 K. For this material one can difinitely say that when

If the magnetic susceptibility of a paramagnetic material at 300 K is 1.2 xx 10^(-4) , then at what temperature it will be 2.4 xx 10^(-5) ?

A physics lab is designed to study the transfer of electrial energy from one circuit to another by means of a magnetic field using simple transformers. Each transformer has two coils of wire electrically insulated from each other but wound a round a common core of ferromagnetic material. The two wires are close together but do not touch each other The primary (1^(@)) coil is connected to a source of alternating (AC) current. The secondary (2^(@)) coil is connected to resistor such as a light bulb. The AC source produces on oscillating voltage and current in the primary coil that produces an oscillating megnetic field in the core. material. This in turn induces an oscillating voltage and AC curent in the secondary coil Students collected the following data comparing the number of turns per coil (N) , the voltage (V) and the current (I) in the coils of three transformers. |{:("Transformer","primary coil","Secondary coil"),(1,100 . 10V.10A,200.20V.5A),(2,100.10V.10A,50.5V.5A),(3,100.10V.10A,100.5V.20A):}| A 12 V battery is used to supply 2.0 mA of current to the 300 turns in the primary coil of a given transformer. What is the current in the secondary coil if N_(2) = 150 turns.

A physics lab is designed to study the transfer of electrial energy from one circuit to another by means of a magnetic field using simple transformers. Each transformer has two coils of wire electrically insulated from each other but wound a round a common core of ferromagnetic material. The two wires are close together but do not touch each other The primary (1^(@)) coil is connected to a source of alternating (AC) current. The secondary (2^(@)) coil is connected to resistor such as a light bulb. The AC source produces on oscillating voltage and current in the primary coil that produces an oscillating megnetic field in the core. material. This in turn induces an oscillating voltage and AC curent in the secondary coil Students collected the following data comparing the number of turns per coil (N) , the voltage (V) and the current (I) in the coils of three transformers. |{:("Transformer","primary coil","Secondary coil"),(1,100 . 10V.10A,200.20V.5A),(2,100.10V.10A,50.5V.5A),(3,100.10V.10A,100.5V.20A):}| The primary coil of a transformer has 100 tunrs and is connected to a 120 V AC source. How many turns are in the secondary coil if there is 2400 V across it

A physics lab is designed to study the transfer of electrial energy from one circuit to another by means of a magnetic field using simple transformers. Each transformer has two coils of wire electrically insulated from each other but wound a round a common core of ferromagnetic material. The two wires are close together but do not touch each other The primary (1^(@)) coil is connected to a source of alternating (AC) current. The secondary (2^(@)) coil is connected to resistor such as a light bulb. The AC source produces on oscillating voltage and current in the primary coil that produces an oscillating megnetic field in the core. material. This in turn induces an oscillating voltage and AC curent in the secondary coil Students collected the following data comparing the number of turns per coil (N) , the voltage (V) and the current (I) in the coils of three transformers. |{:("Transformer","primary coil","Secondary coil"),(1,100 . 10V.10A,200.20V.5A),(2,100.10V.10A,50.5V.5A),(3,100.10V.10A,100.5V.20A):}| A trasnsformer with 40 turns in its primary coil is connected to a 120 V AC source. If 20 W of power if supplied to the primary coil, how much power is developed in the secondary coil ?