Home
Class 12
PHYSICS
An iron sample having mass 8*4kg is repe...

An iron sample having mass `8*4kg` is repeatedly taken over cycles of magnetisation and demagnetisation at a frequency of `50cps`. It is found that energy of `3*2xx10^4J` is dissipated as heat in the sample in 30 minutes. If the density of iron is `7200kg//m^3`, calculate the value of energy dissipated per unit volume per cycle in the iron sample.

Text Solution

Verified by Experts

Here, `m=8*4kg`, `v=50c//s`, `rho=7200kgm^-3`
Volume `=m/rho=(8*4)/(7200)=1*167xx10^-3m^3`,
Energy dissipated in 30 minutes `=3*2xx10^4J`
Energy dissipated/sec `=(3*2xx10^4)/(30xx60)=17*78Js^-1`
Energy dissipated/volume/cycle `=(17*78)/(1*167xx10^-3xx50)=304*7Jm^-3cycl e^-1`
Promotional Banner

Topper's Solved these Questions

  • MAGNETIC EFFECT OF CURRENT AND MAGNETISM

    PRADEEP|Exercise Conceptual Problems (d)|2 Videos

  • MAGNETIC EFFECT OF CURRENT AND MAGNETISM

    PRADEEP|Exercise Very Short Answer Questions (a)|2 Videos

  • ELECTROSTATICS

    PRADEEP|Exercise ASSERTION-REASON TYPE QUESTIONS|2 Videos

  • OPTICS

    PRADEEP|Exercise Multiple choice questions|1 Videos

Similar Questions

Explore conceptually related problems

An iron sample having mass 8*4kg is repeatedly taken over cycles of magnetisation and demagnetisation at a frequency of 50c//s . It is fount that 3*2xx10^4J of energy is dissipated as heat in the sample in 30min . If density of iron is 7200km//m^3 , what is the hysterisis loss?

An iron sample weighing 8*4kg is taken through repeated cycles of magnetisation and demagnetisation at a frequency of 50c//s . In 30 minutes, energy dissipated as heat in the sample is 3*2xx10^4J . If density of iron is 7200kg//m^3 , what is the energy dissipated per unit volume per cycle?

The hyterisis loss for a sample of 12kg is 300Jm^-3cycl e^-1 . If density of iron is 7500kg//m^3 , calculate energy loss per hour at 50cycl e//sec .

A piece of iron of mass 8.4 kg is repeatedly magnetised and demagnetised by an external periodic time varying magnetic field of frequency 50Hz. In the iron piece it is measured that rate of heat dissipation is 6.4xx10^(4)J//hr . If iron density is 7200Kg//m^(3) find the energy dissipated in iron piece per cycle per unit volume of it.

A specimen of iron weighing 6kg loses 8*64xx10^4J of energy per hour when subjected to 50c//s a.c. If density of iron is 6000km//m^3 , what is the hysterisis loss per unit volume per cycle?

Hysterisis loss for a sample of 120kg is 300Jm^-3//cycl e . Frequency of supply is 50cycl e//s . If density of iron is 7500kg//m^3 , find energy loss in 60 minutes.

State Joule's law of heating and give its mathematical form. An electric iron takes a current of 5A and develops 1.5 xx 10^(4) J of heat energy in 30 s. Calculate the resistance of the electric iron.

One kg of a diatomic gas is at pressure of 8xx10^4N//m^2 . The density of the gas is 4kg//m^3 . What is the energy of the gas due to its thermal motion?

Strain energy of a wire is 1.8 xx 10^(-3) J and strain energy per unit volume of the same wire under the same conditions is 6 xx 10^(-3) J//m^(3) . The volume of the wire will be

Two kg of a monoatomic gas is at a pressure of 4 xx 10^(4) N//m^(2) . The density of the gas is 8 kg//m^(3) . What is the order of energy of the gas due to its thermal motion ?