(a) 
According to Newton's second law, the force experienced by each balloon is given by:
F = ma
where
m = 0.021 kg is the mass
a = 1.1 m/s^2 is the acceleration
Substituting, we found:

The electrostatic force between the two balloons can be also written as

where
k is the Coulomb's constant
Q is the charge on each balloon
r = 16 m is their separation
Since we know the value of F, we can find Q, the magnitude of the charge on each balloon:

(b)
electrons
The magnitude of the charge of one electron is

While the magnitude of the charge on one balloon is

This charge can be written as

where N is the number of electrons that are responsible for this charge. Solving for N, we find:

aumenta su velocidad de 60 a 100 Km/h en 20 segundos. Calcular la fuerza resultante que actúa sobre el coche y el espacio recorrido en ese tiempo
Answer:
281.25 J
Explanation:
We are told that the two objects with masses m and 3m.
Also that energy stored in the spring is 375 joules.
Now, initially the centre of mass of the system took place at rest, it means v1 = v and v2 = v/3
Thus, from principle of conservation of energy, we have;
½mv² + ½(3m)(v/3)² = 375J
(m + 3m/9)½v² = 375
(4/3)m × ½v² = 375
Multiply both sides by ¾ to get;
½mv² = 375 × ¾
½mv² = 281.25 J
Therefore, energy of lighter body is 281.25 J
Answer:
rotation
Explanation:
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