Ampres law is often written contourintegral B vector (r vector) middot dl vector = mu_0I_enclosed. The integral on the left is

(A) the integral throughout the chosen volume.
(B) the surface integral over the open surface.
(C) the surface integral over the closed surface bounded by the loop.
(D) the line integral along the closed loop.
(E) the line integral from start to finish.

(C) line integral along a closed loop

This integral is evaluated by dividing the path into infinitesimal segments dL, calculating the scalar product B•dL for each segment, and sum these products. The component of B parallel to dL at each point is always used in evaluating this integral.

The line integral is equal to mu_o × I.

Explanation:

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.