The functions that would be performed both by the placenta and the hatchery so that the embryos will survive is to maintain the temperature of the embryos. The temperature should also be at the temperature where the embryos would thrive and develop.
The force of attraction between 2 charged spheres can be explained by Coulomb's law,
It states the force of attraction is directly proportional to the magnitudes of the charges and inversely proportional to the square of the distance between the charges.
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where F - force of attraction/repulsion
q₁ and q₂ - charges of the 2 spheres
k - Coulomb's law constant
r - distance between the spheres
In the question given, the charges of the spheres remain constant in both instances, only distance changes. Therefore (kq₁q₂) = c which is a constant
then F = c / r²
first instance
6 x 10⁻⁹ N = c/ (20 cm)² ---1)
F = c/(10 cm)² --- 2)
2) / 1)

F = 6 x 10⁻⁹ x 4
F = 2.4 x 10⁻⁸ N
Answer:
Change in momentum is 1.1275 kg-m/s
Explanation:
It is given that,
Mass of the ball, m = 274 g = 0.274 kg
It hits the floor and rebounds upwards.
The ball hits the floor with a speed of 2.40 m/s i.e. u = -2.40 m/s (-ve because the ball hits the ground)
It rebounds with a speed of 1.7 m/s i.e. v = 1.7 m/s (+ve because the ball rebounds in upward direction)
We have to find the change in the ball's momentum. It is given by :




So, the change in the momentum is 1.1275 kg-m/s