On a foggy day,two drivers spot each other wh | vedclass

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(A) Convert speeds to $m/s$: $u_1 = 70 	imes \frac{5}{18} = \frac{350}{18} \approx 19.44\, m/s$ $u_2 = 60 	imes \frac{5}{18} = \frac{300}{18} \appro

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The collision will be averted

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(A) Convert speeds to $m/s$: $u_1 = 70 	imes \frac{5}{18} = \frac{350}{18} \approx 19.44\, m/s$ $u_2 = 60 	imes \frac{5}{18} = \frac{300}{18} \approx 16.67\, m/s$ Relative initial velocity $u_{rel} = u_1 + u_2 = \frac{650}{18} \approx 36.11\, m/s$. Relative retardation $a_{rel} = 5 + 5 = 10\, m/s^2$. Using $v^2 - u^2 = 2as$,for the collision to be averted,the stopping distance $s$ must be less than or equal to $80\, m$. $0^2 - (36.11)^2 = 2(-10)s$ $s = \frac{1304}{20} = 65.2\, m$. Since the required stopping distance $65.2\, m$ is less than the initial separation $80\, m$,the collision will be averted.

On a foggy day,two drivers spot each other when $80\, m$ apart. They were travelling at $70\, km/h$ and $60\, km/h$. Both apply brakes simultaneously which retard the cars at the rate of $5\, m/s^2$. Which of the following statements is correct?

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