Distance & Time Conversions to remember:
1 km = 1000 meters
1 hour = 60 mins = 3600 sec
1 meter = 100 cms
1 mile = 1760 yards
1 yard = 3 feet
1 mile = 5280 feet
1 mph(miles per hour) = 1 * 1760 /1 * 3600 = 22/45 yards/sec
1 mph(miles per hour) = 1 * 5280/1* 3600 = 22/15 feet/sec
1 mile = 1.609 km = 1609 meters (for calulation purpose, value of mile can be approximated to 1600 meters)
Kilometer/hour(km/hr) to Meter/Second(m/s) conversion:
a km/hr = a * 5/18 m/s
Meter/Second(m/s) to Kilometer/hour(km/hr) conversion:
a m/s = a * 18/5 km/hr
Formulae:
Speed = Distance traveled/time taken; Time taken = Distance traveled / Speed ; Distance Traveled = (Speed x Time taken).
If the ratio of the speeds of A and B is a : b, then the ratio of the
the times taken by then to cover the same distance is 1/a : 1/b or b : a.
Suppose a man covers a certain distance at x km/hr and an equal distance at y km/hr. Then,
the average speed during the whole journey is (2xy/(x+y)) km/hr
Two objects A and B moving along a circular path ion the same direction, having started simulataneously and from the same point traveling at speeds of a and b will meet again when faster oibject has gained one full circle over the slower object
That is : when the time * relative speed (a-b) equals one complete round.
The 2 objects will again meet at the starting point at a time which is the LCM of the time taken for each of the objects indiidually to complete one round.
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