Punjab Physics 2018 Paper 1 — Solved Past Paper with Answers

Q1. Maximum compton shift is observed at:

• A. 0°
• B. 90°
• C. 180°
• D. 45°✓

Explanation: Explanation will be added soon!

Q2. Bremsstrahlung radiations are example of:

• A. Atomic spectra
• B. Molecular spectra
• C. Continuous spectra
• D. Discrete spectra✓

Explanation: Explanation will be added soon!

Q3. What is different in isotopes?

• A. number of protons
• B. number of neutrons
• C. number of electrons
• D. Charge number✓

Explanation: Explanation will be added soon!

Q4. Circulation of blood is studied by radio isotope:

• A. carbon-14
• B. carbon-12
• C. cobalt-60
• D. sodium-24✓

Explanation: Explanation will be added soon!

Q5. if electric lines of force are equally spaced the electric field is:

• A. uniform
• B. non-uniform
• C. weak
• D. strong✓

Explanation: Explanation will be added soon!

Q6. Drum of Photocopier is made of:

• A. Copper
• B. Toner
• C. Selenium
• D. Aluminium✓

Explanation: Explanation will be added soon!

Q7. Magnetic effect of current is used in:

• A. Toaster
• B. Electric motor
• C. Electric iron
• D. D.C battery✓

Explanation: Explanation will be added soon!

Q8. Two current carrying parallel conductors are lying in same direction, they

• A. form magnetic dipole
• B. attract each other
• C. repel each other
• D. have no effect✓

Explanation: Explanation will be added soon!

Q9. If current flowing through a solenoid becomes four times, then magnetic field inside it becomes:

• A. two times
• B. three times
• C. four times
• D. half✓

Explanation: Explanation will be added soon!

Q10. In A.C, inductor behaves as:

• A. Capacitor
• B. Resistor
• C. Commutators
• D. Transistor✓

Explanation: Explanation will be added soon!

Q11. In A.C generator when plane of coil is perpendicular to the magnetic field, then output of generator is:

• A. NWAB
• B. 2πf
• C. maximum
• D. zero✓

Explanation: Explanation will be added soon!

Q12. In metal detectors, we use:

• A. RL circuit
• B. RC circuit
• C. LC circuit
• D. any of these✓

Explanation: Explanation will be added soon!

Q13. In frequency modulation, which factor is changed?

• A. Amplitude of carrier waves
• B. Frequency of carrier wave
• C. Amplitude of signal
• D. Frequency of signal✓

Explanation: Explanation will be added soon!

Q14. A material which is insulator at OK and conduct at room temperature is:

• A. Silver
• B. Lead
• C. Germanium
• D. Polythene✓

Explanation: Explanation will be added soon!

Q15. Doping is made compartively larger in:

• A. emitter
• B. base
• C. collector
• D. P-type semi-conductors✓

Explanation: Explanation will be added soon!

Q16. In put resistance of op-amplifier is of the order of:

• A. Few ohms
• B. Mega ohms
• C. Milli ohms
• D. Micro ohms✓

Explanation: Explanation will be added soon!

Q17. Light of 4.5ev is incident on a cesium surface and stopping potential is 0.25V, maximum K.E of emitted electrons is:

• A. 4.5ev
• B. 4.25ev
• C. 4.75 ev
• D. 0.25 ev✓

Explanation: Explanation will be added soon!