Statement A: Cyclones may be caused due to wind travelling at high speed owing to difference in air Pressure.Statement B: The destruction of a cyclone depends only on its location.

____ may be caused due to wind travelling at high speed due to difference in air pressure

The destruction of a cyclone depends mainly on its i) intensities, ii)sizeiii)location. iv) time of occurance

Statement A convection involves flow of matter within a fluid due to unequal temperatures of its parts. Statements B A hot bar placed under a running tap water loses heat due to effect of convection with in water. Statement C Heat transfer always involves temperature different between two systems. Identify the correct option.

(A): Two waves moving in a uniform string having uniform tension cannot have different velocities. (R): Elastic and intertial properties of string are same for all waves in same string. Moreover speed of wave in a string depends on its elastic and inertial properties, pressure only.

(A) Source motion effects the wavelength but observer motion effects the number of waves received by him (B) The apparent change in frequency depends on the distance between source and observer (C) The echo and the direct note differ both in speed and intensity The correct statements are

A fully loaded boeing aircraft has a mass of 3.3 times 10^5 Kg . Its total wing area is 500 m^2 . It is in level flight with a speed of 960 km//h (a) Estimate the pressure difference between the lower and upper surfaces of the wings (b) Estimate the fractional increase in the speed of the air on the surface of the wing relative to the lower surface.[ The density of air is p= 1.2 kg m^-3 ]