Answer:
(a) 
(b) 15 hours
Explanation:
half life, T = 12 hours
No = 19 g
(a) Let N be the amount remaining after time t.
Let λ be the decay constant.
The equation of radioactivity used here is given by
(b) N = 8 gram
Substitute the values in above equation
λ = 0.0577 per hour
So, 
Take natural log on both the sides
- 0.0577 t = - 0.865
t = 15 hours
Answer:
q1 = q₂= -3
therefore each sphere has the same charge of -3 untis
Explanation:
The metallic spheres have mobile charge, so when the two spheres come into contact the total charge
Q_total = q₁ + q₂
Q_total = -2 -4
Q_total = -6 units
it is distributed in between the two spheres evenly since the charges of the same sign repel each other.
When the spheres separate each one has
q₁ = -6/2
q1 = q₂= -3
therefore each sphere has the same charge of -3 untis
Known values; mass per / volume and mass of each atom
average volume=<span> volume per atom. </span>
<span>density*mass per atom = volume per atom </span>
<span>1cm^3 / 7.87 gram * 9.27 *10^-26 kg /atom* 1000 gram / kg=
</span>=<span>1.178 * 10^-22 cm^3 per atom </span>
<span>Convert that to mass </span>
<span>1 cm^3 * (1 m / 100 cm)^3 </span>
average volume= <span>1.178 *10^-29 m^3 per atom </span>
<span>distance: </span>
<span>Volume of a cube is L^3 </span>
<span>so L = (1.178*10^-29)^(1/3) </span>
<span>Half way through the cube is distance 1/2 L. </span>
<span>Second cube is 1/2 L </span>
<span>So distance between the center of 2 cubes = L </span>
=2.28 *10^-10 m
Answer:
Mix
Explanation:
A battery has two electrodes, at one end it has the anode and the other end has the cathode. Electrons travel through the circuit from the anode (negative) to the cathode (positive), and this is the driving force that provides electricity to flow through circuits.
The anode needs to have a low electron affinity because it needs to readily release electrons, and the cathode needs to have a high electron affinity because it needs to readily accept electrons.
Answer:
C
Explanation:
There's a reason newton's 3rd law is called action-reaction :D
A - 1st law/inertia
B - 2nd law/f=ma
