Answer:

Explanation:
Let say the empty wagon has mass "M"
now by newton's II Law we will have

now it is given that empty wagon is pulled with acceleration 1.4 m/s/s
now we will have

now a child of mass three times the mass of wagon is sitting on the empty wagon
so here we have


so we have

Answer:
The answer to your question is: F = 0.4375 N. The force will be 16 times lower than with the first conditions.
Explanation:
Data
F = 7 N
F = ? if the masses is quartered
Formula

Process
Normal conditions F = Km₁m₂/r² = 7
When masses quartered F = K(m₁/4)(m₂/4)/r² = ?
F = K(m₁m₂/16)/r²
F = K(m₁m₂/16r² = 7/16 = 0.4375 N
Answer:
The mass of the copper is 3.00kg
Explanation:
It is C, Left the Meet after her events were over
As wavelength increase, frequency decrease