Answer:
(a) 45 micro coulomb
(b) 6 micro Coulomb
Explanation:
C = 3 micro Farad = 3 x 10^-6 Farad
V = 15 V
(a) q = C x V
where, q be the charge.
q = 3 x 10^-6 x 15 = 45 x 10^-6 C = 45 micro coulomb
(b)
V = 2 V, C = 3 micro Farad = 3 x 10^-6 Farad
q = C x V
where, q be the charge.
q = 3 x 10^-6 x 2 = 6 x 10^-6 C = 6 micro coulomb
Answer: 1.55 x 10⁴ Nm²c^-1
Explanation: The electric flux, electric field intensity and area are related by the formulae below.
Φ= EAcosθ,
Where Φ= electric flux (Nm²c^-1)
E =electric field intensity (N/m²)
A = Area (m²)
θ= this is angle between the planar area and the magnetic flux
For our question E=3.80KN/c= 3800 N/c
A= 0.700 x 0.350= 0.245m²
θ= 0° ( this is because the electric field was applied along the x axis, thus the electric flux will be parallel to the area).
Hence Φ= 3800 x 0.245 x cos(0)
= 3800 x 0.245 x 1 (value of cos 0° =1)
= 1.55 x 10⁴ Nm²c^-1
Thus the electric field is 1.55 x 10⁴ Nm²c^-1
Answer:
c. 
Explanation:
= Initial distance between asteroid and rock = 7514 km = 7514000 m
= Final distance between asteroid and rock = 2823 km = 2823000 m
= Initial speed of rock = 136 ms⁻¹
= Final speed of rock = 392 ms⁻¹
= mass of the rock
= mass of the asteroid
Using conservation of energy
Initial Kinetic energy of rock + Initial gravitational potential energy = Final Kinetic energy of rock + Final gravitational potential energy

Newton’s first law of motion, also called the law on inertia, states that an object continues in its state of rest or of uniform motion unless compelled to change that state by an external force.Newton’s second law of motion states that if a net force acts on an object, it will cause an acceleration of that object.Newton’s third law of motion<span> states that for every action there is an equal and opposite reaction. hope this wasnt two long!</span>
The advantage is that we do not run out of resources and a disadvantage is that is dangerous when a “human” gets too close and gets sick by the radiation.