Find the number density of impurity atoms that must be added to a pure silicon crystal inorder to convert it to have resistivity (i) `10^(-1)Omegam` n-type silicon (ii) `10^(-1)Omegam` p-type silicon. Give for silicon: `mu_(e)=0.135m^(2)V^(-1)s^(-1)`
and `mu_(h)=0.048m^(2)V^(-1)s^(-1)`.

Find the number density of impurity atoms that must be added to a pure silicon crystal inorder to convert it to have resistivity (i) 10^(-1) Omega m n-type silicon (ii) 10^(-1) Omega m p-type silicon. Give for silicon: mu_(e) =0.135 m^(2)V^(-1)s^(-1) and mu_(h) =0.048 m^(2)V^(-1)s^(-1) .

A battery of emf 2V is connected across a block of length 0.1m and area of cros-section 1xx10^(-4)m^(2) . If the block is of intrinsic silocon at 300K , find the electron and hole currents. What will be the magnitude of the total current? What will be the magnitude of the total current if germanium is used instead of silicon? Given that for Si at 300K : mu_(e)=0.135m^(2)V^(-1)s^(-1),mu_(h)=0.048m^(2)V^(-1)s^(-1) and intristic carrier concentration n_(i)=1.5xx10^(16)m^(-3) . For Ge at 300K: mu_(e)=0.39m^(2)V^(-1)s^(-1),mu_(h)=0.19m^(2)V^(-1)s^(-1) and n_(i)=2.4xx10^(19)m^(-3)

A semiconductor has the electron concentration 0.45 xx 10^(12) m^(-3) and hole concentration 5 xx 10^(29) m^(-3) . Find its conductivity . Given electron mobility = 0.135 m^(2) V^(-1) s^(-1) and hole mobility = 0.048 m^(2) V^(-1) s^(-1) , e = 1.6 xx 10^(-19) C

The resistance of a wire of length 330m and cross-section area 1.0 mm^(2) made of material of resistivity 1.0 xx 10^(-7) Omegam is: