Question

when a car driver travelling at an initial velocity of 100 m/s applies brakes and beings the car of rest in 20 second, what will be its acceleration?​

Answer 1

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Given,

• Initial velocity, u = 100 m/s
• Final velocity, v = 0 m/s
• Time taken, t = 20s

To find,

• its acceleration

Solution,

Acceleration, a = $\sf{ \frac{v - u}{t}}$

$\implies$$\sf{ a = 0 - \frac{100}{20}}$

$\implies$$\boxed{\bf{a = - 5 m/s^{2}}}$

Retardation (negative acceleration) = -5 m/s²

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Extra Information:-

What is retardation?

$\mapsto$Retardation means negative acceleration . The velocity of a body may increase or decrease .

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About Acceleration:-

• Acceleration is the rate of change of velocity of an object.
• The S.I unit for acceleration is meter per second square or m/s².

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Formula of acceleration:-

$\implies$${\bf{\frac{change in velocity}{Time taken}}}$

$\diamond$$\boxed{\bf{\frac{v-u}{t}}}$

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