If a car at rest accelerates uniformly to a speed of 144

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If a car at rest accelerates uniformly to a speed of 144 km/h in 20 s, it covers a distance of

1. 2880 m
2. 1440 m
3. 400 m
4. 20 m

Correct Option: C

Initial velocity of car (u) = 0
Final velocity of car (v) = 144 km/hr = 40 m/s
Time taken = 20 s
We know that, v = u + at
40 = a × 20 ⇒ a = 2 m/s²
Also, v² – u² = 2as

⇒ s =	v² – u²
	2a

⇒ s =	(40)² – (0)²	=	1600	= 400 m
	2 × 2		4