Which of the following is the most usable form of nitrogen to plants?

ammonia

nitrates

nitrous oxide

nitrogen gas

The specific heat of iron is 0.11 cal (g° c. a cafeteria fork made of iron has a mass of 20 grams. how much heat energy is needed to raise the temperature of this fork from 25°c to 75°c?

What will happen to thermal condictivity of a substance if its thickness is doubled? Also give reason.

A ball is dropped from rest from the top of a cliff that is 15.0 m high. From ground level, a second ball is thrown straight upward at the same instant that the first ball is dropped.

The electric force between two charged balloons is 0.12 newtons. If the distance between the two balloons is halved, what will be the new force?

What is the force of string when 5kg and 12 m/s

The force in Newtons on a particle directed along the x-axis is given by F (x) = exp ( - (x/5) + 5) for x≥0 where x is in meters. The particle is constrained to move along the x-axis.

What are electromagnetic waves? what are its characteristics? how do we classify them?

A gas is collected from a radioactive material; upon inspection, the gas is identified as helium. The presence of the helium indicates the radioactive sample is most likely decaying by: A). alpha B). beta + C). beta - D). gamma

Is 30 minutes to nine the same as 30 minutes after 8 in life

In a car changes its philosophy from 32 km/hour to54 km/hour in 8.0 seconds, what is its acceleration?