Explanation:
Cut off wavelength is given by
$\lambda_{\text{min}}=\frac{\text{hc}}{\text{eV}'}$
where h = Planck's constan
c = speed of light
e = charge on an electron
V = potential difference applied to the tube
When potential difference (V) applied to the tube is doubled, cutoff wavelength
$\big({\lambda}'_\text{min}\big)$ is given by
${\lambda}'_\text{min}=\frac{\text{hc}}{\text{e}(2\text{V})}$
$\Rightarrow\lambda'_\text{min}=\frac{\lambda_\text{min}}{2}$
Cuttoff wavelength does not depend on the separation between the filament and the target.
Thus, cutoff wavelength will be halved if the the potential difference applied to the tube is doubled.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
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(c) Number of free electrons |
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(b) -2.5 volt/m |
(c) 2/5 volt/m |
(d) -2/5 volt/m |
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
In an electrolysis experiment, a current i passes through two different cells in series, one containing a solution of 
and the other a solution of 
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(a) In the ratio of the densities of Cu and Ag |
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(b) In the ratio of the at. weights of Cu and Ag |
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(c) In the ratio of half the atomic weight of Cu to the atomic weight of Ag |
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(d) In the ratio of half the atomic weight of Cu to half the atomic weight of Ag |
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(a) |
(b) |
(c) |
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