A) \[\frac{1}{8}h\]
B) \[\frac{1}{4}h\]
C) \[\frac{1}{2}h\]
D) \[1\,h\]
Correct Answer: C
Solution :
Let car B catches car A after t sec, then Distance travelled by A in t sec = Distance travelled by B in t sec \[\Rightarrow \] \[60\,t+2.5=70\,t-\frac{1}{2}\times 20\,{{t}^{2}}\] \[\Rightarrow \] \[10\,{{t}^{2}}-10\,t+2.5=0\] \[\Rightarrow \] \[{{t}^{2}}-t+0.25=0\] or \[t=\frac{1\pm \sqrt{1-4\times (0.25)}}{2}=\frac{1}{2}h\]You need to login to perform this action.
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