1. With an increase in temperature, magnetic susceptibility of a ferromagnetic material ___________
a) Increases
b) Decreases
c) Remains constant
d) First increases and then decreases
Explanation: Magnetic susceptibility of a ferromagnetic material decreases with increase in temeprature.
2. With an increase in temperature, magnetic susceptibility of an anti-ferromagnetic material ____________
a) Increases
b) Decreases
c) First decreases and then increases
d) First increases and then decreases
Explanation: Susceptibility of an anti-ferromagnetic material is first increases and then decreases with increase in temperature.
3. With an increase in the area of hysteresis curve, power loss will __________
a) Increases
b) Decreases
c) First decreases and then increases
d) First increases and then decreases
Explanation: Power loss is directly proportional to the area of hysteresis curve.
4. Magnetic Bubbles are used as __________
a) Storage device
b) Strain gauge
c) Thermostat
d) Potentiometer
Explanation: Magnetic bubbles are small magnetized areas used as storage devices (data bites). One good thing about magnetic bubbles are they do not disappear when power is turned off
5. The polymerization of two or more chemically similar monomers forming a long molecular chain is termed as ____________
a) addition polymerization
b) copolymerization
c) condensation polymerization
d) step-growth polymerization
Explanation: Addition polymerization (also called as chain-growth polymerization) involves addition of two or more ‘similar’ monomers to form a long chain molecule. In, addition polymerization, empirical formula is the same as that of monomer. Polyolefins are formed through addition polymerization.
6. The polymerization of two or more chemically different monomers forming a long molecular chain is termed as ____________
a) addition polymerization
b) copolymerization
c) condensation polymerization
d) chain growth polymerization
Explanation: Copolymerization involves polymerization of two or more different monomers to form a long chain molecule. A well-known ‘Nylon 66’ is a copolymer of hexamethylenediamine and adipic acid.
7. The polymerization of two or more chemically different monomers forming a cross link polymer along with a by-product (can be either water or ammonia) is termed as ___________
a) addition polymerization
b) copolymerization
c) condensation polymerization
d) chain growth polymerization
Explanation: Condensation polymerization (also called as step-growth polymerization) involves condensation (losing small molecules as by-products, usually such as water, methanol and ammonia) of different monomers to form a cross linked polymer. In, condensation polymerization, empirical formula is different as that of monomer. Polymers like polyamides, polyacetals and proteins are formed through condensation polymerization.
8. Which of the following additive is used as an initiator in polymerization reaction?
a) Benzoyl peroxide
b) Mica
c) Glass powder
d) Hydrogen peroxide
Explanation: Addition polymerization involves three steps for form an addition polymer, known as initiation, propagation and termination. In the initiation step, an initiator like hydrogen peroxide, easily split to form two species with a free electron attached to each.
9. Thermosetting plastics have ____________
a) 1-Degree bond
b) 2-Degree bond
c) 3-Degree bond
d) 0-Degree bonds
Explanation: A thermosetting plastic is a polymer which gets irreversibly hardened when heated. They have a three-dimensional network of ‘1-degree’ primary bond. A well-known example of this kind are bakelite, polyester and epoxy resin, etc.
10. Which of the following is a primary bond network of thermosetting plastics?
a) 1-Dimensional
b) 3-Dimensional
c) 2-Dimensional
d) 0-Dimensional
Explanation: Thermosetting plastics have a three-dimensional network of ‘1-degree’ primary bond.