281: Seismic waves that vibrate perpendicular to the direction of their path:
(a) Travel through the solid parts of the earth only
(b) Travel through the solid as well as other parts of the earth
(c) Spread on the surface of the earth
(d) None of the above
282: Which one of the following figures will generate a cone when rotated about one of its straight edges ?
(a) An equilateral triangle
(b) A sector of a circle
(c) A segment of a circle
(d) A right-angled triangle
283: A solid cube just gets completely immersed in water when a 0.2 kg mass is placed on it. If the mass is removed, the cube is 2 cm about the water level. What is the length of each side of the cube?
(a) 12 cm
(b) 10 cm
(c) 8 cm
(d) 6 cm
284: Retina in the eyes acts as a ........ in the camera.
(a) Lens
(b) Shutter
(c) Film
(d) None of these
285: Which one of the areas marked as A, B, C and D in the given figure of the cyclone, witnesses heavy torrential short-duration rainfall accompanied by thunderstorms ?
(a) A
(b) B
(c) C
(d) D