Answer:
0.3967mg of sodium-24 are left
Explanation:
If the half life of radioactive element (which is sodium-24 here) is , then at the end of this time the number of atoms in the sample will become half i.e. 1/2 .
if the original amount of atoms is N°. The formula for calculating the remaining atoms (N) left in the sample after t half lives would be:
Here, in this question,
Given amount of sodium-24 = N° = 13 grams
Half life of sodium-24 = t = 15
and Remaining amount of sodium after 45 hours = N = ?
Therefore, using the given Forumla:
Answer:
Explanation:
We can solve the problem by using Snell's law:
where
n1 = 1.33 is the index of refraction of the first medium (water)
n2 = 1.00 is the index of refraction of the second medium (air)
is the angle of incidence of the wave in water
is the angle of refraction of the wave in air
Solving for the angle of refraction,
Answer:
c. 20 amps.
just divide the watts by the volts
Answer:
a) 1.67 m/s
b) 23kJ
Explanation:
We need to apply the linear momentum conservation formula, that states:
in this case:
the initital kinetic energy is:
and the final:
The energy lost is given by: