The sum of angles in a regular pentagon is
180*(5 - 2) = 540°
Each internal angle is 540/5 = 108°.
Each vertex creates a line of symmetry to the midpoint of the opposite side,
as shown in the figure.
Answer: 5 lines of symmetry.
Answer:
d) 1/4 F
Explanation:
The magnitude of electrostatic force between stationary charges is described by Coulomb's law. This law states that this force is proportional to the magnitudes of the charges:
When each of the spheres has lost half its initial charge, we have:
So, the new electrostatic force is:
Answer:
ve = 8.06 x 10^5 m/s
vp = 1.882 x 10^4 m/s
Explanation:
K = 1.85 eV = 1.85 x 1.6 x 10^-19 J = 2.96 x 10^-19 J
me = 9.11 ✕ 10^-31 kg,
mp = 1.67 ✕ 10^-27 kg
Let the speed of electron is ve and the proton is vp.
For electron :
K = 1/2 me x ve^2
2.96 x 10^-19 = 0.5 x 9.11 x 10^-31 x ve^2
ve^2 = 6.498 x 10^11
ve = 8.06 x 10^5 m/s
For proton:
K = 1/2 mp x vp^2
2.96 x 10^-19 = 0.5 x 1.67 x 10^-27 x vp^2
vp^2 = 3.5449 x 10^8
vp = 1.882 x 10^4 m/s
A.) LUNAR MARIA..............
I'm not sure what your question is. But, the half life is the amount of time required for half the material to decay. For U238 this is 4.5 billion years, whilst for Fr-223 (Francium) its about 22 minutes. To calculate the time for something to decay you need to use the equation:
Mass (after time t) = Mass (initial) * (0.5)^(time/half life)
Hope this helps
