Energy required to remove an electron from aluminium surface is 4.2 eV. If light of wavelength 2000 Ao falls on the surface, the velocity of the fastest electron ejected from the surface will be

see full answer

High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET

🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.

An Intiative by Sri Chaitanya

8.4×105m/sec

7.4×105m/sec

6.4×105m/sec

8.4×106m/sec

answer is A.

(Unlock A.I Detailed Solution for FREE)

Detailed Solution

By using E=Wo+12mvmax2whereE=123752000=6.18eV⇒6.18eV=4.2eV+12mvmax2⇒1.98eV=12mvmax2⇒1.98×1.6×10−19=12×9.1×10−31×vmax2⇒vmax=8.4×105m/s

Watch 3-min video & get full concept clarity