QUESTION 2 Two identical Insulated, graphite-coated polystyrene spheres are suspended from
threads. The spheres are held a small distance apart. The charges on the Sphere P
and Q are -2,4 nC and + 5,6 nC respectively.
P
When the spheres are released they move towards each other.
2.1 Explain why the spheres move towards each other
when they are released.
The two spheres now touch each other and then separate.
2.2 Calculate the charge on each sphere after they touch
and separate.
2.3 Write down the number of electrons found on Sphere
P after it touched Q and separated.
2.4 Which way will electrons move? Write only from P to
Q. or from Q to P, or neither way?
2.5 Explain your answer to Question 6.4.
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2.1 The spheres move towards each other because unlike charges attract, while like charges attract

2.2 +1.6 nC each

2.3 -9.98641451914 × 10⁹ electrons

2.4 P to Q

2.5 Sphere Q has a higher electric potential than Sphere P, therefore electrons move from P to sphere Q

Explanation:

The given parameters are;

The number of charges spheres in the system  = 2 spheres

The type of spheres = Identical spheres

The charges on the spheres;

The charge on sphere, P, q₁ = -2.4 nC

The charge on sphere, Q, q₂ = +5.6 nC

2.1 The spheres move towards each other because unlike charges attract, while like charges attract each other

However, when the spheres touch each other, the sum of the charges are equally distributed across both spheres until they both have the same amount and type of charge and therefore have no net attraction and repel each other

2.2 The charge on the each sphere after they separate, Q = (q₁ + q₂)/2

∴ Q = (-2.4 nC + 5.6 nC)/2 = +1.6 nC

The charge on the each sphere after they separate, Q = +1.6 nC

2.3 The charge of an electron, e = -1.602176634 × 10⁻¹⁹ C

The number of electrons found on Sphere P after separation, 'n', is given as follows;

n = 1.6 × 10⁻⁹/(-1.602176634 × 10⁻¹⁹) ≈ -9986414519.14

The number of electrons found on Sphere P after separation, n = Less 9.98641451914 × 10⁹ electrons

2.4 Sphere P is negatively a charged while Sphere Q is positively charged, therefore, there are more electrons in Sphere P, than positively charged ions and electrons will move from;

P to Q

2.5 Sphere Q is positively charged and has lost electrons and it is electron deficient having a high affinity for electrons, while Sphere P is negatively charged and therefore has an excess amount of electrons

Therefore, due to the electric potential difference between Sphere Q and Sphere P, current will move from the high electric potential sphere, Sphere Q to Sphere P while electrons will move in the reverse direction, which is from Sphere P to Sphere Q.