The mass number of a certain atom is the combined number of proton and neutrons. For a sodium atom, the number of proton is 11 and the number of neutron is also 11 (if this sodium is neutral). Thus, the mass number is 22. Then, there combines another particle with 2 protons and 2 neutrons, the new mass number is equal to 26.
Answer:
I see no eaquations?
It should be matter=constant
The one that's completely submerged is displacing more water, so the buoyant force on it is greater.
funny, actually, i'm a hydraulic, and pneumatic cylinder, pump, and line system mechanic, and the answer is pressure.... pressure builds up from the hydraulic pump, and then transfers through hoses to extend, and contract the cylinders by filling them with hydraulic fluid, and vice versa for contracting them.
hope this helps!
Answer: the external agent must do work equal to -1.3 × 10⁻⁸ J
Explanation:
Given that;
Mass M1 = 7.0 kg
r = 3.0/2 m = 1.5 m
Mass M2 = 21 kg
we know that G = 6.67 × 10⁻¹¹ N.m²/kg²
work done by an external agent W = -2GM2M1 / r
so we substitute
W = (-2 × 6.67 × 10⁻¹¹ × 21 × 7) / 1.5
W = -1.96098 × 10⁻⁸ / 1.5
W = -1.3 × 10⁻⁸ J
Therefore the external agent must do work equal to -1.3 × 10⁻⁸ J
