In the absence of air, why does the horizontal component of velocity for a projectile remain constant while the vertical component changes

Copper has free electrons per cubic meter. a 71.0-cm length of 12-gauge copper wire that is 2.05 mm in diameter carries 4.85 a of current. (a) how much time does it take for an electron to travel the length of the wire? (b) repeat part (a) for 6-gauge copper wire (diameter 4.12 mm) of the same length that carries the same current. (c) generally speaking, how does changing the diameter of a wire that carries a given amount of current affect the drift velocity of the electrons in the wire?

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

What is the relationship between the direction of motion of the balloon and the wind currents