Two positive charges of magnitude 20 micro C and 100 micro C are placed at a distance of 150cm. Calculate the electric force of repulsion between them.

Ablock having mass m slides down an inclined plane. the force of friction between the block and the inclined plane is f, the block's weight is m g, and the normal force is n. (a) draw a free – body force diagram showing the forces acting on the block. (b) write down all relevant newton’s equations for a given situation.

(a) if the pressure in gas is doubled while its volume is held constant, by what factor do (i) vrms and (ii) change? (b) is it possible to boil water at room temperature (20oc) without heating it? explain.

Which is not true of the intertropical convergence zone? a) it features heavy precipitation b) it's where the trade winds collidec) it's a high-pressure zone with sinking air d) it is also known as the doldrums