False
Explanation:
Called an asteroid for many years, Ceres is so much bigger and so different from its rocky neighbors that scientists classified it as a dwarf planet in 2006. Even though Ceres comprises 25 percent of the asteroid belt's total mass, tiny Pluto is still 14 times more massive.
Answer:
a) 6.4 x 10^-12 cm^3
b) 17 x 10^-6 mm^2
Explanation
a). The shape is assumed to be spherical The volume = volume of a sphere = \frac{4}{3} \pi r^3
3
4
πr
3
V = \frac{4}{3}*3.142* 1.15^3
3
4
∗3.142∗1.15
3
= 6.3715 μm^3
1 μm^3 = 10^-12 cm^3
6.3715 μm^3 = 6.3715 x 10^-12 cm^3
==> 6.4 x 10^-12 cm^3
Answer:
Explanation:
20.05 √Tk = 20.05 √355.8 = 378.196... ≈ 378 m/s
Answer:
a)The approximate radius of the nucleus of this atom is 4.656 fermi.
b) The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527
Explanation:

= Constant for all nuclei
r = Radius of the nucleus
A = Number of nucleons
a) Given atomic number of an element = 25
Atomic mass or nucleon number = 52


The approximate radius of the nucleus of this atom is 4.656 fermi.
b) 
k=
= Coulombs constant
= charges kept at distance 'a' from each other
F = electrostatic force between charges


Force of repulsion between two protons on opposite sides of the diameter



The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527