Physics-
General
Easy
Question
In a race for 100m dash, the first and the second runners have a gap of one metre at the mid way stage. Assuming the first runner goes steady, by what percentage should the second runner increases his speed just to win the race.
- 2%
- 4%
- More than 4%
- Less than 4%
The correct answer is: More than 4%
Let 
, 
be the initial speeds of first and second runners. Let 
be time by them when the first runner has completed 50m. During this time, the second runner has covered a distance 
m.
So, 
(i)
Suppose, the second runner increases his speed to 
so that he covers the remaining distance 
m) in times . So
or 
or 
or 
or 
or % increase 
.1%
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