[المواعزيه]

ممكن احد يحل هذه الاسئلة
2-Co–60 is a beta emitter with a half-life of 5.3 years. Approximately what fraction of
Co–60 atoms will remain in a particular sample after 26.5 years?
a) 1/32*
b) 1/26
c) 1/64
d) 1/16

3-The carbon–14 activity of some ancient Indian corn was found to be 7.0
disintegrations per minute (dpm) per gram of carbon. If present-day plant life has 16
dpm per gram of carbon, how old is the Indian corn? t1/2 = 5,730 yr.

a) 2,500 yr
b) 6,800 yr*
c) 4,700 yr
d) 7,200 yr

وفي سؤال كمان 23,56 كيف نحلة وهو مااعطاني atomic mass