In a photoelectric emission experiment,the stopping potential for a given metal is $V$ volt,when radiation of wavelength $\lambda$ is used. If radiation of wavelength $2 \lambda$ is used with the same metal,then the stopping potential (in volt) will be. [Given: $c = \text{velocity of light}$,$e = \text{charge on electron}$,$h = \text{Planck's constant}$]

• A
  $V - \frac{hc}{2e\lambda}$
• B
  $V + \frac{hc}{2e\lambda}$
• C
  $\frac{V}{2}$
• D
  $2V$