An X-ray tube operates at a potential of 2500 V. If the power of the tube is 750 W, calculate the speed of the electron striking the target. [e = 1.6 x 10\(^{-19}\) C; mass of electron = 9.1 x 10\(^{-3}\) kg]

(a) Write down the names of two particles used in explaining the wave nature of matter.

(b) State the wave characteristics which are exhibited by the particles named in (a) above.

 (s) State the Heisenberg Uncertainty Principle.
(b) The product of the uncertainties in Heisenberg Uncertainty Principle is equal to or greater than a constant. State the mathematical expression for this constant.

(a) Distinguish between perfectly elastic collision and perfectly inelastic collision.

(b) Sketch a distance — time graph for a particle moving in a straight line with:

(i) uniform speed;

(ii) variable speed.

(c) A body starts from rest and travels distances of 120, 300 and 180m in successive equal time intervals of 12 s. During each interval the body is uniformly accelerated. (i) Calculate the velocity of the body at the end of each successive time interval.

(ii) Sketch a velocity-time graph for the motion.

(a) Explain the terms: (i) inertia; (ii) inertial mass.

(b) List three factors which affect the rate of evaporation of water in a pond.

(c) Two ice cubes pressed together for some time were found to stick together when the pressure was removed. Explain this observation.

(d) Two vertical capillary tubes of the same diameter are lowered into beakers situated at the same level, containing liquids A and B of densities 9.2 x 10\(^2\) kgm\(^{-3}\) and 1.30 x 10\(^3\) kgm\(^{-3}\) respectively. A suction pump is used to withdraw air from the top of the liquid columns in the tubes by means of a T-piece arrangement until the liquid in A rises to a height of 26.0 cm. Calculate the height of the liquid in tube B.