DISTANCE

The source is at some distance from an obstacle. Distance between obstacle and the point of observation is b and wavelength of light is lambda . Then the average distance of nth Fresnel zone will be at a distance …from the point of observation.

Total distance between A and B is d kms . If the distance travelled along the stream is three time of the total distance and the distance travelled against the stream is two times of the total distance . If the time taken to cover the distance along the stream is 10% less then the time taken to cover the distance against the stream .if a person cover a distance of 21 km in 1 hr 24 min along the stream , then find the rate of current ?

Anil travels from place A to place B and Akhil travels form place A. Anil travels one- third of the distance and Akhil travels one-fourth of the distance. The distance travelled by Anil is one kilometre more than the distance travelled by Akhil. What is the distance between place A and place B ? (In km)

Twons A,B and C are on a straight line. Town C is between A and B. The distance A to B is 100 km. How far is A from C ? (i) The distance from A to B is 25% more than the distance from C to B. (ii) The distance from A to C is 1/4 of the distance from C to B.

A particle moves in a straight line from A to B (a) for the first half of distance with speed v_(1) and the next half of distance with speed v_(2) . (b) for the first one-third distance with speed v_(1) and the next two-third distance with speed v_(2) . (c ) for the first one-fourth distance with speed v_(0) , the next half of distance with speed 2v_(0) and the last one-fourth distance with speed 3v_(0) . Find the average speed in each case.