Answer:
At night we experience quietness more. At this time, sounds of object will be heard more clearer
The final mass after decay can be obtained by using under given relation:
half life period of As-81 = 33 seconds
mf = mi x (1/2^n)
= 100 x ( 1/2^(43.2/33))
= 40.4 %
According to another source this is what I got
<span>0.735 J ( Ep-potential energy, m-mass,g-gravitational acceleration = 9.81m/s², h-height; Ep = m * g * h; Ep = 0.0300 kg * 9.81 m/s² * 2.5 m )
</span>Hope it helps
