How does the electrical conductivity of an intrinsic semiconductor change as temperature rises?
Correct answer A. Increases
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Everyday Science MCQs
Page 169 of Everyday Science multiple-choice questions with answers. Tap an option to check yourself.
Page 169 of 198
Which of these has the largest energy gap between its valence and conduction bands?
Correct answer C. Non-metals
What is a band that is completely filled with electrons called?
Correct answer A. Core band
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The band theory of solids satisfactorily explains the nature of which materials?
Correct answer D. All of the above
What is it called when the density of atoms in a crystal is the same along any direction?
Correct answer D. Homogeneity
The angles between the faces stay the same in every sample of a given crystal. What is this property called?
Correct answer C. The external symmetry of form
What are materials called whose valence electrons are tightly bound to their atoms at low temperature?
Correct answer B. Insulators
Under which condition does a ferromagnetic material become fully magnetised?
Correct answer B. Alternating current at its peak value
What name is given to the energy band occupied by the valence electrons?
Correct answer A. Valence band
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What is the process of joining small molecules to form a large molecule called?
Correct answer A. Polymerisation
A force F stretches a wire and produces an extension l. The energy stored in the wire equals ½Fl only on which condition?
Correct answer D. The extension of the wire is proportional to the force applied
If the ratio of stress to strain is the Young’s modulus of a material, how is the tension in a wire related to its extension?
Correct answer A. Directly proportional to extension
A wire hanging vertically is stretched by 1 mm when a 20 N weight is hung from its lower end. How much energy does the wire store?
Correct answer C. 0.01 J
A force applied to one end of an elastic wire produces a strain α. If Y is the Young’s modulus of the wire’s material, how much energy is stored per unit volume of the wire?
Correct answer A. ½Yα²
A wire of length L is stretched by an extension E when a force F is applied at one end. If the elastic limit is not exceeded, how much energy is stored in the wire?
Correct answer C. ½FE
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Which of these quantities does not have the dimensions of force per unit area?
Correct answer B. Strain
Which dimensional formula represents stress?
Correct answer D. ML⁻¹T⁻²
Which of these substances has the highest elasticity?
Correct answer D. Steel
By which method can biomass be turned into fuel?
Correct answer C. Both A and B
Which type of cell converts solar energy directly into electrical energy?
Correct answer B. Photovoltaic