The perception-reaction time for a vehicle travelling at

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The perception-reaction time for a vehicle travelling at 90 km/h, given the coefficient of longitudinal friction of 0.35 and the stopping sight distance of 170 m (assume g = 9.81 m/s²), is ____________ seconds.

1. 1.151 s
2. 2.215 s
3. 3.151 s
4. 4.024 s

Correct Option: C

3.1 to 3.2

SSD = 0.278Vt +	(0.278V)²
	2gf

HO = 0.278 × 90 × t +	(0.278 × 90)²
	2 × 9.81 × 0.35

∴ t = 3.151 s