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A nucleus $_n X ^m$ emist one -$ \alpha $ Particle and two $\beta$ Particle. The resulting nucleus is
$_nX^m \rightarrow _{n-2}X^{m-4} \rightarrow _nY^{m-4}$
Af a certain time, a radio active sample contains $2 \times 10^{20}$ atoms and disintegration rate is $3 \times 10 ^ {10}$ atom persec. When$2 \times 10^{15}$ atoms are Left to decay its disintegation rate will be
${dN \over df} = df \Rightarrow I = dN$ $ I^1 = \lambda N_1 $ $ I_2 = \lambda N_2 $ $ {I_1 \over N_1} = \lambda $ $ {I_1 \over N_2} = \lambda $ $\therefore {I_1 \over N_1} = { f_2 \over N_2} \Rightarrow I_2 = { I_2 \over N_1} \times N_2 = { 3 \times 10^{10} \times 2 \times 10^{15} \over 2 \times 10_20} = 3 \times 10^5 $
excited hydrogen atom emits a Photon of wave length in returning to the ground state The quantum number n of exilted state is given by
$ {1 \over \lambda} R [{ 1 \over 1 ^2 } - { 1 \over n^2 } ] $ $ {1 \over \lambda } = R [ 1- { 1 \over n^2 } ]$ $ { 1 \over \lambda } = R - { R/ n^2}$ $ { R \over n^2 }= R -{1/ \lambda } = { \lambda R -1 \over \lambda }$ $ { R \over n^2 } = { \lambda R -1 \over \lambda}$ $ n^2 = { \lambda R \over \lambda R -1 }$ $ n = \sqrt {\lambda R \over \lambda R -1}$
The radius of Ge nuclide is measured to be twice the radius of $_4^9Be$ . The number of nucleons in Ge are
$ R = Ro(a)^{1/3} = 2R = Ro(A){1/3}$ $ \therefore { 1 \over 2 } = ({ 9 \over A }) ^ { 1/3} = { 1 \over 8 } = { 9 \over A} \Rightarrow \therefore A =72 $
Find the value of r if I = 1 A and potential difference across PQ is 1V
Vsq=i3×1+rI3
where Vsq=26/
Therefore, r = 25Ω
A silicon optical fibre with a care diameter large enough has a care refractive inder of 1.50 and cladding refractive inder 1.47. The critical angle at the care cladding interface is
An insulater ared in a transmission line has dierectrie unstant equal to 0.25 What is the velocity factor of the transmission line ?
What is the working principal of optical fibre ?
A photo director area light of wavelength 1400nm Band gap of the Semiconductor used in the photo detector is -----------$ ( h = 6.63 \times 10 ^ {-34} JS ; C = 3 \times 10 ^ 8 m/s )$
The velocity of e.m. waves in a medium is $ 2.5 \times 10 ^ 8 ms^ {-1}$ what is the dielectric constant of the medium ?
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.