Punjab Group of Colleges
Test (chapter 17)
Physics (B)
Time: 40 mins
Marks: 20
(Objective Part) (1x6)
You have four Choices for each objective type Question as A, B, C and D. Please encircle
the right answer.
NOTE: Attempt All Questions.
(i) The process of adding a small amount of impurity into the pure semiconductor material is;
A. Mixing
B. Doping.
C Casting.
D. Extracting.
(ii) which of them is not a crystalline solid ;
A. Copper .
B. Sodium chloride.
C. Glass .
D. Iron.
(iii) Strain is the ratio of ;
A. Force/Area
B. Area/Force.
C. Change in length/Original Length.
D. Mass/Volume.
(iv)The substances which break just after the elastic limit is reached, are called ;
A. Ductile substance
B. Soft substance
C Brittle substance.
D. Malleable substance
(v) The conduction band in insulator is;
A. Partially filled
B. Fully filled.
C. Empty.
D. All of the above
(vi)A permanent magnet is made of from the material which is;
A. Diamagnetic
B. Ferromagnetic
C. Both A and B.
D. None of the above.
Short Question:
1.
Define stress and strain. What are their S.I units?
2.
What are p-type semiconductors?
3.
What is meant by Diamagnetic and Paramagnetic substances?
Long Question:
What is meant by strain energy? How can it be determined from the force-extension graph?.
A wire 2.5 m long and cross sectional area 1/10⁵ meter square is stretched 1.5 mm by a force of 100
B in the elastic region. Calculate Young’s Modulus