Dry is always more potent, as long as your spices are not old. If you have "fresh" dry ginger, 1 teaspoon would be the right amount to substitute for 2 tablespoons of fresh ginger.
Since ginger is something that loses its potency in dry form very quickly, the best possible answer to this question is "to taste."
The amount yielded from two small pieces of grated ginger root can vary depending on the actual size of the ginger. The average will between 1/4 and 1/2 cup.
About 1% is raw ginger root. Nearer to 2% in ground ginger
103 grams
A one inch piece of fresh, grated ginger (generally yielding 1 tablespoon) equals approximately 1/8 teaspoon ground (dried) ginger. Source: http://www.evitamins.com/healthnotes.asp?ContentID=3602003
1 inch of ginger grated will produce about 4 teaspoons.
Avoid doing this. The proportions unbalance a recipe when you substitute ground for freshly grated ginger.
6mc
I would just use the same amount because ginger paste is basically really finely miced ginger. Maybe cut down a slight amount if your not a huge fan of ginger.
Sources vary. One source says 1 tbsp fresh equals 1/4 tsp ground, another says 1 tbsp fresh equals 1/8 tsp ground (half as much!). So I translate them to either 1/12 tsp of ground or even less (because there are three teaspoons in a tablespoon). How about a few shakes from the jar? That's what I do when the recipe says one teaspoon freshly ground and it hasn't ruined anything yet.
The weight of 1 teaspoon of ground ginger is 0.063 ounces. This is equal to 1.8 grams or 28 grains.
Always use 2 oz. of fresh ground coffee per 12 cups. This equals about 6 tablespoons of fresh coffee. Remember to use fresh cold water in a sparkling clean coffee carafe to enhance aroma and flavour.
Ginger (Fresh) 1 tablespoon, grated or chopped equals a 1-inch piece
The term is for fresh ginger. What you do is get a real ginger root and measure it. One ginger root can be as big as 8 inches long, so you want a piece about as long as your finger. Then you can grate it into your recipe. Most US groceries carry it in the fresh produce department.