Question

The ratio of slopes m1: ro2 of the lines given in the following graphs is, ______.

Options

• charge on electron (e)

• Planck's constant (h)

• specific charge of electron (e/m)

• none of these

Answer 1

charge on electron (e)

Explanation:

For graph (a),

`"(K.E.)"_"max"` = hv - `phi_0`

Hence, comparing with y = mx + C

m =slope= h

`therefore "m"_1 = "h"`

Similarly,

For graph (b),

`"(K.E.)"_"max"` =` "hv"/"e" - phi_0`

`therefore "m"_2 = "h"/"e"`

`therefore` The ratio `"m"_1/"m"_2 = "h"/("h"/"e")` = e