Photo electrons are emitted with a maximum speed of 7xx10^(5)ms^(-1) from a surface when light of frequency 8xx10^(14)Hz is incident on it, the threshold frequency for this surface is :

Photo electrons are emitted with a maximum speed of 7xx10^(5)ms^(-1) f

1.	Photo electrons are emitted with a maximum speed of 7xx10^(5)ms^(-1) from a surface when light of frequency 8xx10^(14)Hz is incident on it, the threshold frequency for this surface is :
Answer» `2.32xx10^(14)Hz` `4.64xx10^(14)Hz` `4.64xx10^(20)Hz` `6.64Hz` SOLUTION :`h(V-v_(0))=(1)/(2) mv_("max")^(2) or v_(0)=v-(mv_("max")^(2))/(2h)` `=8XX10^(14)-(9.1xx10^(-31)xx49xx10^(10))/(2xx6.63xx10^(-34))` `=8xx10^(14)3.63xx10^(14)=4.64xx10^(14)Hz`

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Photo electrons are emitted with a maximum speed of 7xx10^(5)ms^(-1) from a surface when light of frequency 8xx10^(14)Hz is incident on it, the threshold frequency for this surface is :

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