If the fraction of the atoms of a radioactive material left after 120years is 1/64, what is the half-life of the material?

Award0001

2 years ago

Nt/N⁰ = (1/2)^t/T
Nt/N⁰ = 1/64
t = 120 therefore

1/64 = (1/2)^120/T
N.B 1/64 = ½^6. therefore

(1/2)^6 = (1/2)^120/T
cancel out (1/2)

6 = 120/T

T = 120/6 = 20years

Ogunboyowaflorence

3 years ago

My school you guys want to scatter himan being brain abi
it is after 6 half lives not 4
(1/2)^6

mercygracious

2 years ago

I'm confused

Geemah

2 years ago

please can someone explain better
I'm confused

Awo5555

1 year ago

64/2=32
32/2=16
16/2=8
8/2=4
4/2=2
2/2=1
that means the half reduction has occure 6 times in 120years
120/6=20

Bukunmiajibola

9 years ago

I don't understand ooh