(a) 
The gravitational potential energy of the two-sphere system is given by
(1)
where
G is the gravitational constant
is the mass of sphere A
is the mass of sphere B
r = 1.8 m is the distance between the two spheres
Substitutign data in the formula, we find

and the sign is negative since gravity is an attractive force.
(b) 
According to the law of conservation of energy, the kinetic energy gained by sphere B will be equal to the change in gravitational potential energy of the system:
(2)
where
is the initial potential energy
The final potential energy can be found by substituting
r = 1.80 m -0.60 m=1.20 m
inside the equation (1):
U=-\frac{(6.67\cdot 10^{-11})(94 kg)(100 kg)}{1.2 m}=-5.22\cdot 10^{-7} J
So now we can use eq.(2) to find the kinetic energy of sphere B:

Answer:
9.43*10^3 year
Explanation:
For this question, we ought to remember, or know that the half life of carbon 14 is 5730, and that would be vital in completing the calculation
To start with, we use the formula
t(half) = In 2/k,
if we make k the subject of formula, we have
k = in 2/t(half), now we substitute for the values
k = in 2 / 5730
k = 1.21*10^-4 yr^-1
In(A/A•) = -kt, on rearranging, we find out that
t = -1/k * In(A/A•)
The next step is to substitite the values for each into the equation, giving us
t = -1/1.21*10^-4 * In(5.4/15.3)
t = -1/1.21*10^-4 * -1.1041
t = 0.943*10^4 year
Explanation:
This should be of help:
An atom is made up of three subatomic particles:
- Protons are the positively charged particles.
- Electrons are the negatively charged particles.
- Neutrons do not carry any charges.
A neutral atom is an atom that has not lost or gained any amount of electrons.
In a neutral atom;
the number of protons and electrons are the same
Usually atoms are designated this way:
ᵃₙX
where X is the symbol of the atom
a is the mass number of the atom
n is the atomic number of the atom
The mass number = number of protons + number of neutrons
Atomic number = number of protons
Note; atomic number is the same as the number protons and the number of electrons in a neutral atom.
Use this guide to solve the problem
Learn more:
Atomic number brainly.com/question/5425825
#learnwithBrainly
This is kinetic energy to heat energy
The answer is B- the process of cells making new cells