D=-5m
a(gravity)=-9.8m/s^2
vi= 0m/s
t=?
use equation d=vi*t+0.5a*t^2
because vi=0, you can cross out vi*t because anything multiplied by 0= 0
rearrange the equation to say t^2=d/0.5a
t^2= -5/-4.9
t^2=1.02
find the square root...
final answer: t=1s
A mixture is not a pure substance
Answer:
A. F=107.6nN
B. Repulsive
Explanation:
According to coulombs law, the force between two charges is express as
F=(Kq1q2) /r^2
If the charges are of similar charge the force will be repulsive and if they are dislike charges, force will be attractive.
Note the constant K has a value 9*10^9
Hence for a charge q1=7.10nC=7.10*10^-9, q2=4.42*10^-9 and the distance r=1.62m
If we substitute values we have
F=[(9×10^9) ×(7.10×10^-9) ×(4.42×10^-9)] /(1.62^2)
F=(282.4×10^-9)/2.6244
F=107.6×10^-9N
F=107.6nN
B. Since the charges are both positive, the force is repulsive
Well energy absorption by a material depends upon their atomic properties. Energy is absorbed in discrete quanta of energy as predicted by quantum mechanics only if the corresponding energy state is available either it is absorbed by electrons or nucleus depends whether it can go to permissible energy state, if not system can't absorb energy at all.