See first of all I.E is calculated for an isolated atome and not for a molecule...now....for H Zeff =1 and for He Zeff=1.7...hence I.E of he is more than h

SIR,

WHEN A BLOCK IS SLIDING DOWN  A INCLINED PLANE WITH A UNIFORM SPEED ( WHERE ACCLERATION  IS ZERO ) THEN WHAT KIND OF FRICTION  FORCE WILL BE APPLIED THERE.