2) a). The resistivity of a wire varies with its
- length
- area of cross-section
- mass
- material
b) Given the units of a physical quantity. Choose the correctrelation (J is for Joule, V is for volt, C is for Coulomb)
A) J = CV
B) J = VA
C) J = C/A
D) V = J C
c) A charge of 3 C moving in a uniform electric fieldexperiences a force 3000 N. The potential difference between twopoints situated in the field at a distance 1 cm from each otherwill be
A) 10 V
B) 90 V
C) 1000 V
D) 9000 V
d) Choose the only incorrect relation:
A) ampere = coulomb/second
B) volt = coulomb/joule
C) ohm = volt/ampere
D) coulomb = Joule/volt
e) In an astronomical telescope, the image formed by theobjective is I0Â Â and that formed by eye piece isIe . Then
A)I0Â Â andIe are both real
B)I0Â Â andIe are both virtual
C)I0  is virtual andIe  is real
D)I0  is real andIe  is virtual
