Radioactive decay is given by:
N = No x e^(-λt)
We know that N/No has to be 0.05
λ = 0.15
0.05 = e^(-0.15t)
t = ln(0.05)/(-0.15)
t = 19.97 days
v = average speed of movement of the Southwest Indian Ridge = 20 mm/year
d = distance moved by the Southwest Indian Ridge = 100 mm
t = number of years required to move distance "d"
distance traveled is given as
d = v t
inserting the above values in the formula
100 mm = (20 mm/year) t
dividing both side by 20 mm/year
t = 100 mm/(20 mm/year)
t = 5 years
Answer:
1) a substance made by mixing other substances together.
2) diverse in character or content.
3) of the same kind; alike.
4) a means of solving a problem or dealing with a difficult situation.
5) a homogeneous noncrystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.
Answer:
16km/h
Explanation:
Vt=20km/h ---train speed
Vd=4km/h
Donas speed relative to ground is:
Vrd=Vt-Vd
Donas is moving in opposite direction of train .
Vrd=20km/h-4km/h
Vrd=16km/h
