An approximate measurement, generally around 2 tablespoons. When a recipe calls for a knob of butter, it is intended that one can take some liberty, so don't worry about adding an exact amount.
Ginger is a root vegetable with sections sticking out like arms all over it. A knob would be one of the "arms" sticking out of the main body. Depending on the taste you are going for, you might want a large knob or small knob. The knob should be peeled and then either chopped, grated, or sliced.
Ginger.
it already is in cooking measurement if it is in grams
No. Ground ginger is simply ginger, dried and ground, as the name suggests. Crystallized ginger is ginger that has been preserved through cooking and blending with syrup and sugar.
yes
Onions are bulbs, used in cooking as vegetables. Ginger is a rhizome - a horizontal stem of the ginger plant. Tomatoes are a fruit.
Used as a culinary spice when cooking Asian and Jamaican dishes, also used in popular drinks, ginger beer and ginger ale.
tablespoon vs gram
Betty Croker was the inventor of Standardized cooking Measurement.
Romans use ginger spice because it is good foam mainly good for cooking and for herbal medicine
Candied ginger does not have the same pain relieving properties as fresh ginger, but it is still very strong. The cooking of ginger makes it less effective, but it is still a good pain reliever and stomach relaxer.
Japanese food uses different spices as Chinese food, such as wasabi and pickled ginger.
ANSWER just try to use some cooking measurement converter like this one http://www.ghostcalc.com/cooking-measurement-converter.html