Electrical Engineering Materials - Study Mode
[#1] On which of the following factors does the resistivity of a material depend ?
Correct Answer
(D) All of the above
Explanation
Solution: The resistivity $$
ho $$ of a material depends on multiple factors, and all of the mentioned options contribute to it: Resistance of the conductor: The resistivity is directly related to the resistance through the formula $$ R =
ho frac{L}{A} $$, where $$ R $$ is the resistance, $$
ho $$ is the resistivity, $$ L $$) is the length of the conductor, and $$ A $$ is the area of the conductor section. Area of the conductor section: The area of the conductor section $$( A )$$ is present in the denominator of the resistance formula. As the area increases, the resistance decreases, and vice versa. Length of the conductor: The length of the conductor $$( L )$$ is also present in the numerator of the resistance formula. As the length increases, the resistance increases, and vice versa. Therefore, the correct answer is Option D: All of the above .
[#2] Piezoelectric materials serve as a source of ________ .
Correct Answer
(D) Ultrasonic waves
[#3] The tiny block formed by the arrangement of a small group of atoms is called the
Correct Answer
(A) Unit cell
[#4] The number of atoms per unit cell in B.C.C. structure is
Correct Answer
(B) 2
[#5] Which of the following variety of copper has the best conductivity ?
Correct Answer
(C) Pure annealed copper