Question

A car, initially at rest, picks up a velocity of 72 km h$^{-1}$ in 1/4 minute. Calculate acceleration and distance covered by the car​

Answer 1

Answer:

car initially at rest picks up a velocity of 72 km per hour in 20 seconds if ... is 1000 kg find Force developed by its engine and distance covered by car ... Force = mass×acceleration = 1000× 1 = 1000 N.

Answer 2

GivEn:

• Initial Velocity of car, u = 0 m/s
• Final Velocity of car, v = 72 km/h = 20 m/s
• Time taken, t = 1/4 minute = 15 s

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Need to find:

• Acceleration and distance covered by car?

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Solution:

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${\underline{\sf{\bigstar\: According\:to\:the\:question\::}}}$

☯ Using 1st Equation of motion,

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$\star\;{\boxed{\sf{\purple{v = u + at}}}}$

$:\implies\sf 20 = 0 + a \times 15$

$:\implies\sf 20 = 15a$

$:\implies\sf a = \cancel{ \dfrac{20}{15}}$

$:\implies{\boxed{\frak{\pink{a = 1.3\;m/s^2}}}}\;\bigstar$

$\therefore\;{\underline{\sf{Hence,\: Acceleration\:is\: \bf{1.3\;m/s^2}.}}}$

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☯ Now, Using 2nd equation of motion,

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$\star\;{\boxed{\sf{\purple{s = ut + \dfrac{1}{2} at^2}}}}$

$:\implies\sf s = 0 \times 15 + \dfrac{1}{2} \times 1.3 \times (15)^2$

$:\implies\sf s = \dfrac{1}{2} \times 1.3 \times 225$

$:\implies{\boxed{\frak{\pink{s = 146.25\;m/s^2}}}}\;\bigstar$

$\therefore\;{\underline{\sf{Hence,\:the\:distance\:travelled\:by\:car\:is\:{\textsf{\textbf{146.25\:m}}}.}}}$