1 An electric current is the overall movement of charged particles in one direction. 2  To obtain an electric current, there needs to be a continuous circuit from one terminal of a battery to the other. 3  An electric current in a circuit transfers energy from the battery to the circuit components.
A pea gravel walkway or patio costs about $5 per square foot, installed, including a layer of base rock. If you'd like to install it yourself, it will cost half as much.Add in the cost of a header or Bender Board. A wood header is about $5 per linear foot; a metal header is $6 (black metal disappears well).You won't need a header if you're installing gravel against a house, fence, or raised bed.dd in the cost of a header or Bender Board. A wood header is about $5 per linear foot; a metal header is $6 (black metal disappears well). You won't need a header if you're installing gravel against a house, fence, or raised bed.
Presently, gravel prices are 50 cents or 2 dollars per square foot for the aggregates. This would make an average concrete driveway price of $300-$1,200 for 12Ã50-feet or a total of about $10,000-$40,000 for a Â¼ mile long, 2-vehicle-wide concrete driveway.