Complete Question:
Metal sphere A has a charge of − Q . −Q. An identical metal sphere B has a charge of + 2 Q . +2Q. The magnitude of the electric force on sphere B due to sphere A is F . F. The magnitude of the electric force on sphere A due to sphere B must be:
A. 2F
B. F/4
C. F/2
D. F
E. 4F
Answer:
D.
Explanation:
If both spheres can be treated as point charges, they must obey the Coulomb's law, that can be written as follows (in magnitude):

As it can be seen, this force is proportional to the product of the charges, so it must be the same for both charges.
As this force obeys also the Newton's 3rd Law, we conclude that the magnitude of the electric force on sphere A due to sphere B, must be equal to the the magnitude of the force on the sphere B due to the sphere A, i.e., just F.
The hull type that is best for use on ponds, small lakes and calm rivers is Flat Bottom Hull.
A flat bottomed boat is a boat with a flat bottomed, two-chined hull, which allows it to be used in shallow bodies of water, such as rivers, because it is less likely to ground. The flat hull also makes the boat more stable in calm water.
Answer:
The acceleration of the earth is 7.05 * 10^-25 m/s²
Explanation:
<u>Step 1:</u> Data given
mass of the apple = 0.43 kg
acceleration = 9.8 m/s²
mass of earth = 5.98 * 10 ^24 kg
<u>Step 2:</u> Calculate the acceleration of the earth
Following the third law of Newton F = m*a
F(apple) = F(earth) = m(apple)*a(apple)
F(apple) = 0.43 kg * 9.8 m/s² = 4.214 N
a(earth) = F(apple/earth)/m(earth)
a(earth) = 4.214N /5.98 * 10 ^24 kg
a(earth) = 7.05 * 10^-25 m/s²
The acceleration of the earth is 7.05 * 10^-25 m/s²
Answer B would be the correct answer for the questions
Answer:
0.23 s
Explanation:
First of all, let's find the time constant of the circuit:

where
is the resistance
is the capacitance
Substituting,

The charge on a charging capacitor is given by
(1)
where
is the full charge
we want to find the time t at which the capacitor reaches 90% of the full charge, so the time t at which

Substituting this into eq.(1) we find
