The boys body will continue to move in a forward motion, the stairs an an will make the skateboard come to a complete stop because the force of the stairs is much greater, this makes in an unbalanced force. This is and example of inertia of motion.
Answer: The chemical energy of reactants is greater than the chemical energy of products.
Explanation: In the given reaction

It can be seen that the energy has been released. Thus we can say that reactants have converted to products by release of energy. Thus energy of products is less as compared to energy of reactants as some of the energy has been released.
Answer:
A) E = 0N/C
B) 0i + 0^^j
C) F = 0N
D) 0^i + 0^j
Explanation:
You assume that the rings are in the zy plane but in different positions.
Furthermore, you can consider that the origin of coordinates is at the midway between the rings.
A) In order to calculate the magnitude of the electric field at the middle of the rings, you take into account that the electric field produced by each ring at the origin is opposite to each other and parallel to the x axis.
You use the following formula for the electric field produced by a charge ring at a perpendicular distance of r:
(1)
k: Coulomb's constant = 8.98*10^9Nm^2/C
Q: charge of the ring
r: perpendicular distance to the center of the ring
R: radius of the ring
You use the equation (1) to calculate the net electric field at the midpoint between the rings:

The electric field produced by each ring has the same magnitude but opposite direction, then, the net electric field is zero.
B) The direction of the electric field is 0^i + 0^j
C) The magnitude of the force on a proton at the midpoint between the rings is:

D) The direction of the force is 0^i + 0^j
Answer:
The Answer is 0.019998c
Explanation:
Please see the attached Picture for the answer.