Answer:
10 kJ
Explanation:
W = Fd
W = (μN)(vt)
W = μ(mg)vt
W = 0.7(42.9)(9.81)(9)(3.8)
W = 10,075.12506 J
W ≈ 10 kJ
Answer:

Explanation:
<u>Coulomb's Law</u>
The force between two charged particles of charges q1 and q2 separated by a distance d is given by the Coulomb's Law formula:

Where:

q1, q2 = the objects' charge
d= The distance between the objects
We know both charges are identical, i.e. q1=q2=q. This reduces the formula to:

Since we know the force F=1 N and the distance d=1 m, let's find the common charge of the spheres solving for q:

Substituting values:


This charge corresponds to a number of electrons given by the elementary charge of the electron:

Thus, the charge of any of the spheres is:


According to Newton`s law. Force exerted by car,

After adding an additional 400 kg of mass, the force will be same therefore the acceleration

Thus, the acceleration after adding the masses is 1.47 \ m/s^2.
Answer:
d) The stone will have about 50 joules of kinetic energy and 0 joules of potential energy .
Explanation:
Given :
Initial Potential energy ,
.
Initial Kinetic energy ,
. ( because ball is in rest )
Now , we know , kinetic energy is maximum when an object reaches ground .
Also , potential energy is zero when an object is in ground .
We know , by conservation of energy :
Initial total energy = Final total energy

Therefore , option d) is correct .
602.496 J I think, I hope this helps!