Question

The angular momentum of an electron in a given orbit is J, Its Kinetic Energy will be?

Answer 1

According to Bohr

angular momentum of an electron = nh/2(pi)

hence,

mvr = nh/2(pi)

according to question angular momentum is “J”

means

nh/2(pi) = J

now

mvr = nh/2(pi)

squaring both sides

m2v2r2 = n2h2/4(pi)2

m2v2r2 = J2

now knietic energy = 1/2mv2

hence,

multiplying both sides my ½

1/2m2v2r2 = J2/2

1/2mv2 = J2/2r2m

Answer 2

△▼△▼ ђ๏ɭค❣ △▼△▼

According to Bohr,,

angular momentum of an electron = nh/2(pi)

hence,

mvr = nh/2(pi)

according to question angular momentum is “J”

means 

nh/2(pi) = J

now 

mvr = nh/2(pi)

squaring both sides

m2v2r2 = n2h2/4(pi)2

m2v2r2 = J2

now kinetic energy = 1/2mv2

hence,

multiplying both sides my ½

1/2m2v2r2 = J2/2

1/2mv2 = J2/2r2m

✧༺♥༻∞ ђ๏קє ย ɭเкє เՇ♥️ ˚*∞༺♥༻✧