If the specific resistance of a potentiometer wire is 10^-7 Om and current flowing through it is 0.1 amp, cross-sectional area of wire is 10^-6 m², then potential gradient will be ________________.

(a)

10^-2 v/m

(b)

10^-4 v/m

(c)

10^-6 v/m

(d)

10^-8v/m

In an electrical arrangement as shown the equivalent resistance between X and Y will be

(a)

\(158.75\Omega \)

(b)

\(118.75\Omega \)

(c)

\(218.75\Omega \)

(d)

\(318.75\Omega \)

A square aluminum rod is 1 m long and 5 mm on edge. What must be the radius of another aluminum rod whose length is 1 m and which has the same resistance as that of square Aluminum rod?

(a)

1.4 mm

(b)

2.8 mm

(c)

4.2 mm

(d)

5.6 mm

An unknown resistance is connected in parallel with a 15\(\Omega \) resistance and a 12V battery. What is the value of the unknown resistance if the current in the circuit is 2A?

(a)

\(10\Omega \)

(b)

\(20\Omega \)

(c)

\(30\Omega \)

(d)

\(40\Omega \)

How many 160 \(\Omega \) resistor in parallel are required to carry a current of 5 A on a 100 V line?

(a)

2

(b)

4

(c)

6

(d)

8