1. In a gas turbine plant, a gas moving at a velocity of \( 60 \mathrm{~m} / \mathrm{s} \) flows through the turbine at \( 17 \mathrm{~kg} / \mathrm{s} \). the specific enthalpy of the gas at entry is \( 1200 \mathrm{~kJ} / \mathrm{kg} \). the turbine develops 14000 kW of power. The gas leaves the turbine at a velocity of \( 150 \mathrm{~m} / \mathrm{s} \) with a specific enthalpy of \( 360 \mathrm{~kJ} / \mathrm{kg} \). the specific volume at entry is \( 0.6 \mathrm{~m}^{3} / \mathrm{kg} \). determine i. The area of the inlet pipe ii. The rate of heat transfer as the gas passes through the turbine stating whether it is a heat loss ( 6 marks)

3) Choose the correct alternative and rewrite the statement (i) The weight of a body on the earth's surface \( =\ldots \ldots . \). \( \begin{array}{llll}\text { (a) } \frac{G M m}{R} & \text { (b) } \frac{G M m}{R^{2}} & \text { (c) } G M m R^{2} & \text { (d) } \frac{G m}{R^{2}}\end{array} \)

QUESTION 7 (Start on a new page.) 7.1 Reflection of light (and other forms of electromagnetic radiation) occurs when the waves meet a surface or other boundary that does not absorb the energy of the radiation and reflects the waves off the surface. Draw a fully labelled ray diagram to illustrate reflection.

3. Si un ratón y un elefante comen ambos con la misma energía cinética, ¿podrías decir cuál corre más aprisa? Explica tu respuesta en términos de la ecuación de la ECT?

8.4 To produce an emf of 9 V , the area of the coil, with its axis coinciding with the direction of a magnetic field (area perpendicular to magnetic field), is halved in 2 minutes from \( 0.6 \mathrm{~m}^{2} \) to \( 0,3 \mathrm{~m}^{2} \). Calculate the number of turns around the coil.

7.2 A beam of light travels from water to plastic. The speed of light in plastic is \( 2,05 \times 10^{8} \mathrm{~m} \cdot \mathrm{~s}^{-1} \). The refractive index of water is 1,33 . Calculate the refractive index of plastic.