Gujranwala board 2017
PHYSICS
Inter Part-II
Time Allowed: 3 Hours
Note:-Three are THREE sections in this paper i.e. Section A. B and C. Attempt Section-A on the same paper and return it to the superintendent within the given time. No marks will be awarded for Cutting, Erasing or Overwriting. Marks of Identification will lead to UFM case, Mobile Phone etc. are not allowed in the examination hall.
Section A

• In SI units, the value of permittivity of free apace (£0) is

1. 9.10⁹Nm²C²
2. 9.10^-9C²N^-1m^-2
3. 8.85x10¹²C²N^-1m^-2
4. 8.85.10^-12C²N^-1m^-2

• The direction of field lines around an isolated negative charge ‘-q’ is

1. Radially inward
2. Radially outward
3. Elliptical
4. Circular

• The current which flows a point at higher potential to a point at lower potential is called

1. Electric current
2. Conventional Current
3. Either of these
4. None of above

• A current carrying conductor experiences maximum magnetic force in a uniform magnetic field when it is placed

1. Perpendicular to field
2. Parallel to field
3. At an angle of 60° to the field
4. At an angle of 180° to the field

• In current carrying long solenoid the magnetic field produced does not depend upon.

1. The radius of solenoid
2. Number of turns per unit length
3. Current flowing through solenoid
4. All of above

• When a conductor moves across a magnetic field, an emf is set up, this emf is called

1. Variable emf
2. Constant emf
3. Back emf
4. Induced emf

• The motional emf depends upon the

1. Length of conductor
2. Speed of conductor
3. Strength of magnet
4. All of these

• The phase of AC at positive peak from origin is

1. 3π/2
2. π/2
3. π/4
4. π

• In pure capacitor AC circuit the current I and charge q are

1. In phase
2. Out of phase
3. Parallel to each other
4. None of above

• A solid having regular arrangement of molecules throughout its structure is called

1. Amorphous solid
2. Polyrneric solid
3. Glassy solid
4. Crystal solid

• The value of potential barriers for silicon at room temperature is

1. 09.7 V
2. 0.5 V
3. 0.3 V
4. 00.9 V

• The central region of transistor is known as

1. Emitter
2. Base
3. Collector
4. Depletion region

• The theory of relativity was proposed by

1. Newton
2. Maxwell
3. Compton
4. Einstein

• The mass of object will be doubled at speed.

1. 2.6x10⁸m/s
2. 1.6x10⁸m/s
3. 3.6x10⁸m/s
4. 0.6x10⁸m/s

• X-ray diffraction reveals that these are

1. Particle type
2. Wave type
3. Both wave and particle
4. None of above

• Mass of proton is

1. 1.6x10^-27kg
2. 1.6x10^-19kg
3. 1.67x10^-31kg
4. 9.1x10^-31kg

• When a nucleus emits alpha particle, its atomic mass decreases by

1. 1
2. 2
3. 3
4. 4

Subjective part
Section B

Q2: Write short answers to any EIGHT (8) questions.

1. How can you identify that which plate of a capacitor is positively charged?
2. If a point charge q of mass m is released in a non-uniform electric field with field lines pointing in the same direction, will it make rectilinear motion?
3. State Gauss's Law.
4. Define capacitance of a capacitor.
5. Ha charged particle moves in a straight line through some region of space, can you say that the magnetic field in the region is zero?
6. How can you use a magnetic field to separate isotopes of chemical element?
7. Is it possible to orient a current loop in a uniform magnetic field such that the loop not tend to rotation Explain
8. How can you explain the waveform of various voltages formed in CRO?
9. What is the back EMF effect in monks?
10. In a certain reeks: the earth's magnetic field points vertically down, when a plane flies due north, which wingtip is positively charged'?
11. Define mutual induction. Also write down its unit.
12. Is it possible to change both the area of the loop and the magnetic field passing through the loop and still not have an induced emf in the loop

 Q3: Write short answers to any EIGHT (8) questions.

1. Write names of two sources of current.
2. Define temperature co-efficient of resistance and write its formula.
3. Explain why the terminal potential difference of a battery decreases when the current drawn from it is increased?
4. What is the difference between A.C circuit and D.C circuit?
5. Why power is dissipated zero in pure inductive and pure capacitive circuit?
6. Define modulation and write names of its types.
7. Define stress and write its formula.
8. Define elastic limit and yield strength.
9. What are paramagnetic substances?
10. What is OR-GATE? Write its relation.
11. Who charge carriers are not present in the depletion region?
12. What is the effect of forward and reverse biasing of a diode on the width of depletion region?

Q4. Write short answers to any SIX (6) questions.

1. When a solid is heated, it begins to glow? Why it does first appears red?
2. Will higher frequency of light eject greater number of electrons than low frequency of light?
3. What advantages an electron microscope has over an optical microscope?
4. How can the spectrum of hydrogen contain so many lines when hydrogen atom contains one electron? Explain why LASER action could not occur without population inversion between two atomic levels.
5. If a nucleus has a half-life of one year. Does this mean that it will be completely decayed after two years? Explain.
6. A particle which produces more ionization is less penetrating. Why?
7. What factors make a fusion difficult to achieve?
8. How can radioactivity help in the treatment of cancer?
9. When a solid is heated, it begins to glow? Why it does first appears red?
10. Will higher frequency of light eject greater number of electrons than low frequency of light?
11. What advantages an electron microscope has over an optical microscope?

SECTION-C

Note: Attempt any THREE questions.

Q5:

1. Define electric flux. Find electric flux through a surface enclosing charge.
2. The potential difference between the terminals of a battery in open circuit is 2.2 V and 3 when it is connected across a resistance of 5 ohm, the potential falls to 1.8 V?Calculate the current and internal resistance of the battery.

Q6:

1. Derive the expression for torque on current carrying coil in uniform magnetic field.
2. An ideal step down transformer is connected to main supply of 240 V. It is desired to operate a 12V, 30 W lamp. Find the current in the primary and the transformation ratio.

Q7:

1. What is operational amplifier? Discuss the action of op.amp as inverting and non-inverting amplifier.Also calculate voltage gain in each case.
2. A 10 mH. 20  coil is connected across 240 V and Hz source. How much power does it dissipate?

Q8.

1. What is meant by strain energy? How can it be determined from the force extension graph
2. A particle of mass 5 mg moves with a speed of 8 m/s. Calculate its de-Broglie wavelength.

Q9.

1. Explain inner shell transition and production of x-rays.
2. The half-life  of is 9.70 hours. Find its decay constant.