(1). At absolute zero, si acts as

• (a). non-metal
• (b). metal
• (c). insulator
• (d). none of these
• (e). None of these

(2). By increasing the temperature, the specific resistance of a conductor and a semiconductor

• (a). increases for both
• (b). decreases for both
• (c). increases, decreases
• (d). decreases, increases
• (e). None of these

(3). The energy band gap is maximum in

• (a). metals
• (b). superconductors
• (c). insulators
• (d). semiconductors
• (e). None of these

(4). The part of a transistor which is most heavily doped to produce large number of majority carriers is

• (a). emitter
• (b). base
• (c). collector
• (d). can be any of the above three
• (e). None of these

(5). A strip of copper and another of germanium are cooled from room temperature of 80k. the resistance of

• (a). each of these decreases
• (b). copper strip increases and that of germanium decreases
• (c). copper strip decreases and that of germanium increases
• (d). each of these increases
• (e). None of these

(6). In the middle of the depletion layer of a reverse-biased p-n junction the

• (a). electric field is zero
• (b). potential is maximum
• (c). electric field is maximum
• (d). potential zero
• (e). None of these

(7). When npn transistor is used as an amplifier

• (a). electrons move from collector to base
• (b). holes move from emitter to base
• (c). electrons move from base to collector
• (d). holes move from base to emitter
• (e). None of these

• (a). 1
• (b). 2
• (c). 3
• (d). 4
• (e). None of these

• (a). 1
• (b). 2
• (c). 3
• (d). 4
• (e). None of these

• (a). 1
• (b). 2
• (c). 3
• (d). 4
• (e). None of these