What will happen if a collection of positive and negative charges are passed at a high speed through a magnetic field which is perpendicular to the direction of motion of the charges? (Assume that both kind of charges are NOT going to recombine)

The motion of a particle of mass m is described by the relation, y = ut - 1⁄2 gt2, where u is the initial velocity of the particle. The force acting on the particle is

A block of wood 40 cm × 20 cm × 10 cm) is kept on a tabletop in three different positions: (a) with its side of dimensions 20 cm × 10 cm; (b) with its side of dimensions 10 cm × 40 cm; and (c) with its side of dimensions 40 cm × 20 cm. The pressure exerted by the wooden block on the tabletop in these positions is represented by P_A, P_B and P_c, respectively. The pressure follows the trend

Which one of the following metals can be extracted using carbon as reducing agent?