DG Khan board
PHYSICS 2016
Interpart 1
(GROUP 1)
Note:Pour possible answers A, B, C and D to each question are given. The choice which you think is correct that circle in front that question with Marker or Pen ink. 'Lining or filling two or more circles 'will result in zero mat k in that question. Write the letter A, B. C or D in the column.(write correct "option) against each question also. If there k a contradiction in the bubble and hand written answer, bubble option will be considered correct.

• The ratio of dimensions of power to work is:

1. 1: T
2.  T: 1
3.  1 : 
4.  : 1

• The cross product of a vector  with itself results

1.   
2.  
3.  Zero
4. Null vector

• For which pair of angles the range of projectile are equal:

1.   ,  
2.   ,  
3.   ,  
4.    ,

• For a typical rocket, how much mass of rocket is in the form of fuel:

1. 60%
2. 50%
3. 80%
4. 100%

• The unit of solar light intensity is:

1. Watt
2.  Kw   
3.  Watt   
4. J.  

• A wheel of diameter I m makes 60 rev/min. the linear speed of a point on its rim in m is:

1.    
2.   2 
3.   
4.  3 

• The value of a time period of a low flying satellite is:

1. 1 year
2. 84 minutes
3. 28 hours
4. 1 day

• The expression for the orbital speed of a satellite is given by:

• The uni of flow rate is given by:

1.   
2. m
3. 
4. 

• The time period of an oscillating mass spring system is 10 second. If mass attached to spring is doubled then time period becomes:

1.  10 S
2.  20 S
3.  5 S
4.  10  

• Beats cannot be heard if the difference of frequencies is more than:

1. 7 Hz
2. 10 Hz
3. ) 5 Hz
4. 20 Hz

• In an open pipe, the fundamental frequency is given by f=…

• In stationary waves the points which always remain at rest are:

1. Nodes
2. Antipodes
3. Crest
4. Trough

• Constructive interference of two coherent beams is obtained if path difference is:

• The Carnot cycle can be shown by which graph:

1. P - T graph
2. V - T graph
3. P - V graph
4. PV - T graph

• If a convex lens is used as a magnifying glass, which lens will give higher magnification that has:

1. Short size
2. Long focal length
3. Large size
4. Short focal length

• At which of the following temperature a body has maximum internal energy:

1.  -273°C
2.  0 K
3. 273 K
4.  -273 K

SECTION I

Q2: .Attempt any eight part

1.  Name several repetitive phenomenon occurring in nature which could serve as reasonable time standards
2.  Write the dimensions of (a) Pressure (b) Energy
3.  Add the following masses in Kg up to appropriate precision 2.189.0.089. 11.8 and 5.32.
4.  Define (a) Radian (b) Steradian
5. The s vector sum of three vectors gives a zero resultant. What can the orientation of the vectors?
6. Two vectors have unequal magnitudes. Can their sum he zeros? Explain.
7.  Define torque. Write its units and dimensions.
8.  An object is thrown vertically upward. Discuss the sign of acceleration due to gravity. Relative to velocity. While the object is in air.
9.  Define Impulse and show that how it is related to linear momentum.
10.  Motion with constant velocity is a special case of motion with constant acceleration. Is this statement pre? Explain.
11.  What is ballistic missile? Define ballistic trajectory.
12.  Why fog droplets appear to be suspended in air?

 Q3: Attempt any eight parts.

1.  An object has 1 joule of potential energy. Explain what does it mean?
2.  A girl drops a cup from a certain height. Which breaks into pieces? What energy changes are involved?
3.  How many most common methods used for the conversion of biomass into fuel. Write their name is to follow a circular path.
4.  Explain what is meant by centripetal force and why it must be furnished to an object if the object is to follow a circular path.
5.  Show that orbital angular momentum   m V r.
6.  Define angular displacement and write its S.I unit.
7.  Why can we not realize an ideal simple pendulum?
8.  What happens to the period of a simple pendulum? If its length is doubled?
9.  Describe some common phenomena in which resonance plays an important role.
10. How are beats useful in tuning musical instruments?
11.  Why does sound travel faster in solid than in air (gases)?
12.  How stationary waves are produced in a medium?

Q4: Attempt any six parts,

1. What is meant by the diffraction of light?
2. Can visible light produce interference fringes? Explain.
3. An oil film: spreading over wet footpath shown colors. Explain how does it happen?
4. What is difference between magnifying power and resolving power or optical instrument?
5. How the power is lost in optical fiber through dispersion" Explain
6. Define the term internal energy. Discuss in what form it is in ideal gas.
7. Why the average velocity of the molecules in a gas zero but the average of the square of velocity is not zero?
8. Give an example of a process in which no heat is transferred to or from the system but the temperature of the system changes.
9. A thermos flask containing milk m a system is shaken rapidly. Does the temperature of milk rise? Discuss.

SECCION: II

NOTE: Attempt any three questions.

Q5:(A) State and nrove Law of conservation of linear momentum.
(B)  A load of 10.0N is suspended from a clothes line. This distorts the line so that it makes an angle of 15” with the horizontal at each end. Find the tension in the clothes line.

Q6:(A) Define rotational kinetic energy. Also derive an expression for rotational K.F. of disc and a hoop.
(B) An object of mass 6 Kg is travelling at a steady velocity of 5 m. What is its kinetic energy? What will be its kinetic energy if its velocity is doubled?

Q7:(A) State and derive Bernoulli's equation.
(B) Find the average speed of oxygen molecules in the air al S.T.P.

Q8:(A) Define simple harmonic motion. Discuss motion of projection of panicle along. He circle and shots that this motion is simple harmonic.
(B) A stationary wave is established in a string which is 120cm long and fixed at both ends. The string vibrates in four segments at a frequency of 120 Hz Determine its wavelength and the fundamental frequency.

Q9:(A) What is optical fiber? Write its principle and how light is propagated through optical fiber
(B) A light is incident normally on a grating which has 2500 lines per Centimeter. Computer the wavelength of spectral line for which the deviation in second Order is.

DG Khan board
PHYSICS 2016
Interpart 1
(GROUP 2) (OBJECTIVE PART) (NOT Available) (SUBJECTIVE PART) (Section)

Q2: Attempt any eight parts.

1. Define the supplementary unit of plane and solid angle.
2. Check the correctness of relation V= 
3. Differentiate between the precision and accuracy.
4.  How many years in 1 sec?
5.  Define position vector.
6.  If one of the rectangular component of a vector is not zero. Can its magnitude be zero? Explain.
7.  If = .What can you say about the components of two vectors?
8.  Define inertial non inertial frame of references.
9.  Define impulse and show that how it is related to linear momentum.
10.  What is the effect on the speed of lighter plane chasing another when it opens the lire?
11.  At what point or points in its path does a projectile have its maximum speed, its minimum speed.
12.  Why fog droplets appear to be suspended in air?

Q3: Attempt any eight parts.

1.  Calculate the work done in kilo joules in lifting a mass of 10 kg through a vertical height of 10 m.
2. What is dimension power? Also define power?
3.  How can we gain energy from tides?
4.  Show that orbital angular momentum  = mVr.
5.  What is meant by moment of inertia? Explain its significance.
6.  Explain artificial gravity.
7.  Does frequency depends on amplitude for harmonic oscillators? Explain.
8.  What happens to the period of a simple pendulum, if its length is doubled?
9.  Explain free and forced oscillations.
10.  Explain wiry sound travels faster in warm air than in cold air.
11.  How are beats useful in tuning musical instruments?
12.  What are Plc conditions of constructive and destructive interference?

Q4: Attempt any six parts.

1. What are coherent sources under what conditions two or more sources behave as coherent sources.
2. Can visible white light produce interference fringes explain briefly.
3. What is diffraction of light, write grating equation?
4. Define critical angle and total internal reflection.
5. What is the difference between photodiode and light emitting diode?
6. State First Law of thermodynamics, how it is applicable on human body.
7. Define entropy. How it changes with temperature.
8. A thermo, flask containing milk is shaken well, does the temperature of milk rise, explain it.
9. Why the average speed of gas molecules is zero? But the average of the squares of velocities is not zero.

NOTE: Attempt any three question

 Q5:(A) Explain sector addition of a vector by rectangular component method.
(B) A 1500 kg car has its velocity reduced from 20 m to 15 m in 3.0s. How large was the average retarding force.

Q6:(A) Define centripetal force and derive its formula  
 Ten bricks, each 6.0 cm thick and mass 1.5 kg lie flat on a table. How much work is required to stack them one on the top of another?

Q7:(A) State and prove equation of continuity.
(B) Find the average speed of oxygen molecule in the air at S.T.P.

Q8:(A) What is the limitation of Newton's formula for the speed of sound in air? How Laplace correct it?
(B) Find amplitude, frequency and time period by considering the wave equation x - 0.25 cos (n/8) t.

Q9:(A) What is Michelson’s' Interferometer? Give its construction and working.
(B) An astronomical telescope having magnifying power of 5 consists of two thin 'enses 24 cm apart. What is the focal length of lenses?