**12th class physics important long and Shorts Questions** for **exam** preparation is Here, You can Find All the Notes of Physics Short, Long, MCQ important For **all Board**…Students try to give success in Exams than they try to find Important Material about different Subjects for Extra preparation of Exams.

Table of Contents

## Paper: Physics Class: FSc Part – II Chapter: 12+13+14

## 2nd year Class Physics Important Short short Answers

- Prove that 1 eV = 1.6×10-19 J.
- Prove that ohm times farad is equal to the second.
- Show that the interior of a hollow charged sphere is a field-free region.
- Prove that Volt/meter is equal to newton/coulomb
- Define coulomb s law and write the formula in vector form.
- What is a Wheatstone bridge? How can it be used to determine an unknown resistance?
- Fine the heat dissipated through a bulb of 100W is an hour.
- Charges are moving in metals but the current is zero before applying the battery. Why?
- What do you mean by ohmic and non-ohmic substances? Also, make a graph.
- How resistance of the conductor is affected if the length and area are doubled at the same time?
- Why does the picture on a TV screen become distorted when a magnet is brought near the screen?
- Can magnetic fieldset into circular motion the stationary electron? If no then why not.
- How can you say magnetic flux is a scalar quantity? Explain
- A charged particle is projected perpendicular to the magnetic field. What happened to its K.E and linear momentum of the charge?
- A loop of wire is suspended between the poles of a magnet with its plane parallel to the pole faces. What happens if a direct current is put through the coil? What happens if an alternating current is used instead?
- How can you identify which plate of the capacitor is positively charged?
- Electric lines of force never cross. why?
- Do electrons tend to go to a region of high potential or of low potential?
- Does bend in a wire affect its electrical resistance? explain
- Why does the resistance of a conductor rise with temperature?
- Describes a circuit that will give a continuously varying potential
- Why the resistance of an ammeter should be very low?
- Why the voltmeter should have very high resistance?
- How can you use the magnetic field to separate isotopes of chemical elements?
- Writes conditions of maximum and minimum magnetic flux?

#### Long Questions

- A) How does the energy store in a capacitor? Derive an expression for energy
- B) A rectangular bar of iron is 2.0 cm by 2.0 cm in cross-section and 40 cm long Calculate its resistance if the resistivity of iron is 11 x10-8 m.
- A) What current should pass through a solenoid that is 0.5 m long with 10,000 turns of copper wire so that it will have a magnetic field of 0.4T?
- B)What is a potentiometer? Give its construction and theory.
- A) Derive a formula for the magnetic force on a moving electric charge in a magnetic field?
- Find the electric field strength required to hold suspended a particle of mass 1.0 x 10 -6 kg and charge 1.0C between two plates 10.0 cm apart.