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Inter (Part-II) Fedral Board 2013
Physics
Part II (Objective Type)
Time Allowed: 20 Minutes
Max. Marks: 17

Question #1
Circle the correct option i.e. A/B/C/D. Each part carries one mark.

The Electric intensity near an infinite plate of positive charge will be --------

(A) q/€o
(B)
(C) q/A
(D) None of these

One Electron Volt is equal to --------------------------?

(A) 6.25x1018 Joule
(B) 6.25x10-18 Joule
(C) 1.6x10-19 Joule
(D) 1.6x1019 Joule

Ceramic materials exhibit super-conductivity at -------------

(A) 0oC
(B) 273K
(C) 60K
(D) 30K

Which electric bulb has the least resistance?

(A) 60 watts
(B) 100 watts
(C) 200 watts
(D) 500watts

The grid in CRO ------------------?

(A) Controls the number of electrons accelerated by anodes
(B) Controls the brightness of the spot fall on the screen
(C) Both A and B
(D) Deflects the beam of electrons

The frequency of A.C used in Pakistan is ------------------------?

(A) 60CPS
(B) 50CPS
(C) 100CPS
(D) 120CPS

Potentio meter can be used as ----------------------------

(A) Ohm meter
(B) Ammeter
(C) Galvanometer
(D) Potential Divider

To convert a Weston-Type galvanometer into voltmeter, the series resistance is given by ------------------?

(A)
(B)
(C)
(D)

N-Type germanium is obtained by doping intrinsic germanium with --------?

(A) Tetravalent impurity atom
(B) Trivalent impurity atom
(C) Pentavalent impurity atom
(D) Hexavalent impurity atom

Emission of electron by metals on heating is called -------------?

(A) Secondary Emission
(B) Field effect
(C) Photoelectric Emission
(D) Thermionic Emission

Which of the following Is NOT basic operation of Boolean variables?

(A) YES operation
(B) NOT operation
(C) AND operation
(D) OR operation

When X-rays are passed through successive aluminum sheets, their hardness ----------

(A) Decreases
(B) Increases
(C) Remains the same
(D) None of these

If the ionization energy of hydrogen atom is 13.6ev, its ionization potential will be -------------------------

(A)13.6V
(B) 136.0V
(C)3.4V
(D) None of these

One amu is equal to -------------------------?

(A) 931 MeV
(B) 9.31 MeV
(C) 93.1 MeV
(D) 0.931 MeV

Cobalt 60 emits y-rays of energy ---------------------.

(A) 117 MeV
(B) 11.7 MeV
(C) 1.17 MeV
(D) 1.17 BeV

Which of the following statement is CORRECT?

(A) Moderators slow down the neutrons
(B) Moderators bring the neutrons to rest
(C) Moderators absorb the neutrons
(D) Moderators reflect the neutrons

The half life of radioactive element is ------------------

(A) T1/2=0.693/
(B) T1/2=1.43/
(C) T1/2=0.693
(D) None of these

Inter (Part-II) Fedral 2013
Physics
Part II (Subjective)
Time Allowed: 2.10 Hours
Max. Marks: 83

Section I

Q.No.2 Answer any FOURTEEN parts. The answer to each part should not exceed 3 to 4 lines (14 x 3 = 42)

How can you identify that which plate of a capacitor is positively charged?
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 a rectilinear motion?
Why does the resistance of a conductor rise with temperature?
What is Wheatstone Bridge? How can it be used to determine an unknown resistance?
Is it possible to orient a current loop in a uniform magnetic field such that loop will not tend to rotate? Explain
You are asked to design a solenoid that will give a magnetic field of 0.10T, yet the current must not exceed 10.0A. Find the number of turns per unit length that the solenoid should have
Does the induced emf always act to decrease the magnetic flux through a circuit?
A metal rod of length 25cm is moving at a speed of 0.5ms-1 in a direction perpendicular to a 0.25T magnetic field. Find the emf produced in the rod
A circuit contains an iron-cored inductor a switch and D.C source arranged in series. The switch is closed and after an interval reopened. Explain why a spark jumps across the switch contacts.
At what frequency will an indoctor of 1.0 H have a reactance of 500Ω?
What is meant by Hysteresis loss? How is it used in the construction of a transformer?
What is the effect of forward and reverse biasing of a diode on the width of depletion region?
In a certain circuit the transistor has a collector current of 10mA and a base current of 40µ , What is the current gain of the transistor?
A beam of red light and a beam of blue light have exactly the same energy, Which beam contains the greater number of photons?
If an electron and a proton have the same de Brogile wavelength, which particle has greater speed?
Find the speed of the electron in the first Bohr orbit
A tungsten target is struck by electrons that have been accelerated from rest through 40kv potential difference. Find the shortest wavelength of the bremsstrahlung radiation emitted?
The radioactive element 22688Ra has a half-life of 1.6x103 years. Since the Earth is about 5 billion years old how can you explain why we still can find this element in nature?
Why are heavy nuclei unstable

Section-C (Marks 26)

Note: Attempt any TWO question. All question carry equal marks. (2 x 13 = 26)

Question #3
(a) What is temperature co-efficient of Resistance and Resitivity? Derive the equations. (06)
(b) The resistance of an iron wire at 0°C IS 1X10⁴Ω. What is the resistance at 500°C if the temperature co-efficient of iron is 5.2x10^-3 K^-1? (05)
(c) Define electron Volt and find its relation with joule (03)

Question #4
(a) Describe RLC series circuit Derive relation for relation for resonance frequency. Also give any four properties of series resonance.   (07)
(b) What is the resonant frequency of a circuit which includes a coil of inductance 2.5H and capacitance of 40 µF?   (03)
(c) Write a short mote on three phase AC Supply?    (03)

Question #5
(a) What do you know about the Biological effect of radiation? Write in detail. (05)
(b) A 75 kg person receives a whole body radiation does of 24m-rad, delivered by ά particles for which RBE factor is 12. Calculate? (05)

The absorbed energy in joules
The equivalent dose in rem