Can someone help me with this problem?

The driver of a train moving at a speed $v_1$ sights a goods train at a distance d ahead of him on the same track moving in the same direction with a slower speed $v_2$ . He puts on brakes and gives his train a constant retardation $a$ . Which of the following option is correct :

(A) $d\geq\frac{2(v_1 - v_2)^2}{2a}$

(B) $d >\frac{(v_1 - v_2)^2}{2a}$

(D) $d \geq\frac{(v_1 - v_2)}{2a}$

#HelpMe!

Easy Math Editor

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Comments

actually you did not complete the question. i suppose the original question was about avoiding the accident between the two trains , and in that case i find option (B) to be correct.

Shubhabrota Chakraborty - 7 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$