1
COMEDK 2024 Morning Shift
+1
-0

In a given semiconductor, the ratio of the number density of electron to number density of hole is $$2: 1$$. If $$\frac{1}{7}$$th of the total current is due to the hole and the remaining is due to the electrons, the ratio of the drift velocity of holes to the drift velocity of electrons is :

A
$$\frac{2}{3}$$
B
$$\frac{3}{1}$$
C
$$\frac{3}{2}$$
D
$$\frac{1}{3}$$
2
COMEDK 2024 Morning Shift
+1
-0

An ideal diode is connected in series with a capacitor. The free ends of the capacitor and the diode are connected across a $$220 \mathrm{~V}$$ ac source. Now the potential difference across the capacitor is :

A
$$110 \mathrm{~V}$$
B
$$311 \mathrm{~V}$$
C
$$2 \sqrt{110} \mathrm{~V}$$
D
$$\sqrt{220} \mathrm{~V}$$
3
COMEDK 2024 Morning Shift
+1
-0

Though $$\mathrm{Sn}$$ and $$\mathrm{Si}$$ are $$4^{\text {th }}$$ group elements, $$\mathrm{Sn}$$ is a metal while $$\mathrm{Si}$$ is a semiconductor because

A
$$\mathrm{Sn}$$ has more electrons than $$\mathrm{Si}$$
B
The energy gap of $$\mathrm{Sn}$$ is zero volt while that of $$\mathrm{Si}$$ is $$0.07 \mathrm{~V}$$
C
The energy gap of $$\mathrm{Sn}$$ is $$1.1 \mathrm{~eV}$$ volt while that of $$\mathrm{Si}$$ is $$0.07 \mathrm{~V}$$
D
$$\mathrm{Sn}$$ has more holes than $$\mathrm{Si}$$
4
COMEDK 2023 Morning Shift
+1
-0

A transistor is connected in CE configuration. The collector supply is $$10 \mathrm{~V}$$ and the voltage drop across a resistor of $$1000 \Omega$$ in the collector circuit is $$0.5 \mathrm{~V}$$. If the current gain factor is 0.96 , then the base current is

A
$$25_6 \mu \mathrm{A}$$
B
$$20.8 \mu \mathrm{A}$$
C
$$22.5 \mu \mathrm{A}$$
D
$$15 \mu \mathrm{A}$$
EXAM MAP
Medical
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