Inter (Part-II) Faisalabad Board 2015
Physics
Part II (Objective Type)
Time Allowed: 20 Minutes 
Max. Marks: 17

Note: You have four choices for each objective type question as A, B, C and D. The choice which you think is correct; fill that circle in front of that question number. Use marker or pen to fill the circles. Cutting or filling two or more circles will result in zero mark in that question.

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

• At resonance frequency, the impedance of RLC series circuit is:

(a) Maximum
(b) Minimum
(c) Zero
(d) Infinite

• Which one is not present in AC generator?

(a) Carbon brush
(b) Coil
(c) Magnetic field
(d) Split ring

• Lenz's law deals with:

(a) Magnitude of emf
(b) Direction of emf
(c) Direction of induced current
(d) Resistance

• The charges moving perpendicular to magnetic field experience force

(a) Maximum
(b) Minimum
(c) Zero
(d) Infinite

• The brightness of spot in CRO is controlled by:

(a) Anode
(b) Cathode
(c) Grid
(d) Deflecting plates

• The thermostats convert changes of temperature into:

(a) Light energy
(b) Electric voltage
(c) Heat
(d) sound

• Electron volt is the unit of:

(a) Potential
(b) Potential difference
(c) Electric current
(d) Electric energy

• SI unit of permittivity of free space are:

(a) Nm² C^-2
(b) N^-1m³C^-1
(c) C²N^-1m^-1
(d) C²N^-1m^-2

• Charge on an electron is:

(a) 1.6x10^-19C
(b) 1.6 x 10⁺¹⁹ C
(c) 9.1 x 10^-19C
(d) 9.1x 10^-27C

• Half life of a radioactive element T_1/2 is given by:

(a) 0.693 λ
(b) 0.693/λ
(c) λ/0.693
(d) 1/0.693λ

• Ballmer series lies in:

(a) Visible region
(b) Invisible region
(c) Ultraviolet region
(d) Infrared region

• The value of Plank's constant is given by:

(a) 6.63 x 10^-34 Js
(b) 9.1 x10^-31Js
(c) 6.63 x 10^-19 Js
(d) 9.1 x 10^-27 Js

• Compton's effect is associated with:

(a) Gamma rays
(b) Beta rays
(c) X-rays
(d) Positive rays

• Minimum numbers of semi-conductor diodes required for full wave rectification are:

(a) 1
(b) 2
(c) 3
(d) 4

• The potential barriers for germanium at room temperature is:

(a) 3 volt
(b) 0.5 volt
(c) 0.7 volt
(d) 0.9 volt

• In p-type substances, the minority carriers are:

(a) Electrons
(b) Protons
(c) Holes
(d) Neutrons

• In three phase AC generator the phase difference between each pair of coil is:

(a) 45°
(b) 60°
(c) 90°
(d) 120°

Inter (Part-II) Faisalabad Board 2015
Physics
Part II (Subjective)
Time Allowed: 3.10 Hours 
Max. Marks: 83

Section I

2. Attempt any EIGHT short questions. (8 x 2 = 16)

• Describe the force or forces on a positive point charge when placed between parallel plates with opposite and equal charges.
• 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?
• Define electron volt, give its mathematical form.
• State and write the formula of Gauss's law.
• Describe the change in the magnetic field inside a solenoid Carrying a steady current I, if the number of turns is doubled, but the length remains the same.
• If a charge particle moves in a straight line through some region of Space, can you say that the magnetic field in the region is zero?
• Two charged particles are projected into a region where there is Magnetic field perpendicular to their velocities. If the charges are Deflected in opposite directions, what can you say about them?
• Define sweep or time base generator.
• When the primary of a transformer is connected to a.c mains the Current in it (a) is very low if the secondary circuit is open, but (b) Increases when the secondary circuit is closed. Explain these facts.
• Does the induced emf always act' to decrease the magnetic flux Through a circuit?
• In a certain region the earth's magnetic field point vertically down. When a plane flies due to north, which wingtip is positively? Charged?
• How can you minimize the power loss in transformer?

3. Attempt any EIGHT short questions. (8 x 2 = 16)

• A potential difference is applied across the ends of a copper wire. What is the effect on the drift velocity of free electrons by (a) Increasing the potential difference (b) decreasing the length and temperature of the wire?
• What are the difficulties in testing whether the filament of lighted Bulb obeys Ohm's law?
• What is Wheatstone bridge? How it be used to determine Unknown resistance?
• Explain the conditions under which electromagnetic waves are Produced from source?
• In a R-L circuit will the current lag or lead the voltage? Illustrate Your answer by a vector diagram.
• Write two properties of RLC series circuit.
• Distinguish between crystalline and amorphous.
• What is difference in elasticity and plasticity?
• Write a note on super conductor.
• The anode of a diode is 0.2v positive with respect to its cathode. Is it forward biased?
• Why ordinary silicon diodes do not emit light?
• Why is the base current in a transistor very small?

4. Attempt any SIX short questions. (6 x 2 = 12)

• Define special theory of relativity and write its postulates.
• Which has the lower energy quanta? Radio waves or x-rays.
• If an electron and a proton have the same de-Broglie wavelength, Which particle has greater speed?
• Define met stable state.
• What do we mean when we say that the atom is excited?
• What do you understand by background radiations? State two Sources of three radiations.
• Which radiation dose would deposit more energy to your body? (a)10m Gy to your hand, or (b) 1mGy to your entire body?
• Define fission and fusion reaction.
• What are hadrons? Give examples.

SECTION-II

Attempt any TIIREE questions. (8 x 3 =24)

Question #5
(a) What is a capacitor? Derive relation for the energy density in Terms of electric field in the capacitor.
(b) How many electrons pass through an electric bulb in one? Minute if 300mA current is passing through it?

Question #6
(a) What is transformer? Describe its principle, construction and Theory.
(b) A coil of 0.1m x 0.1m and of 200 turns carrying a current of 1.0mA is placed in a uniform magnetic field of 0.1T. Calculate the maximum torque that acts on the coil.

Question #7
(a) What is R-C series circuit? Find the impedance of R-C series Circuit .
(b) A 1.25cm diameter cylinder is subjected to a load of 2500kg. Calculate the stress on the bar in mega Pascal’s.

Question #8
(a) What is operational amplifier? How OP-Amplifier is used as Inverting amplifier? Find its gain.
(b) An electron is accelerated through a potential difference of 50v. Calculate its de-Broglie wavelength.

Question #9
(a) Give the postulates of Bohr's model of hydrogen atom. Also Give de-Broglie's interpretation of Bohr's orbits.
(b) If: 233 U decays twice by alpha emission, what is the resulting Isotope ?

SECTION-III

Attempt an .Four questions. (4x2=8)

Question #10 (a) Attempt any four parts:

• A 100cm long wire of area of cross-section 0.002m2 having Resistance 6n. Find its resistivity.
• Sketch the table to find the resistance of galvanometer by half Deflection method.
• What is the potentiometer? Give its one use.
• What is voltmeter?
• What do you mean by reverse biasing of a diode?
• Write the truth table of AND gate.
• Why the resistance of filament of a lamp varies with the rise of Current ?
• Define the term capacitance and give its unit.

(b) Write down the procedure to find the resistance of galvanometer by half deflection method.

OR

Write the method to study the relation between current and Capacitance when different capacitors are used in an AC circuit.

(c) Answer the questions given under the graph.

(i)What do you infor from the graph?
(ii) Find the resistance of a wire with the help of graph.

OR

(i) What do you conclude from the graph?
(ii) Find the slope of the graph.