Question

A car travelling 70 km/hr slows
down to 50 km/hr in 30
minutes. What is its
acceleration?​

Answer 1

Answer:

- 40 km/hr^2 It's negative acceleration or Retardation

Step-by-step explanation:

Final speed = 50 km/hr

original speed = 70 km/hr

Time = 30 minutes = 0.5 hrs

Acceleration = final speed - original speed / time

= 50- 70 / 0.5

= -40 km/ hr^2

Answer 2

${\large{\bf{\red{\clubs{\underline{Given :}}}}}}$

• Car travelling at = u = 70km/hr
• Car slows down to = v = 50km/h
• Time = 30min or 0.5hrs

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${\large{\bf{\blue{\clubs{\underline{To Find :}}}}}}$

• Acceleration = ?

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${\large{\bf{\orange{\clubs{\underline{Solution :}}}}}}$

Formula for acceleration :

${\blue{\boxed{\maltese{\pink{\pmb{Acceleration = \frac{v - u}{t} }}}}}}$

Here,

• U = initial velocity
• V = final velocity
• T = Time

Than,

${\mapsto{\bf{Acceleration = \frac{v - u}{t} }}}$

${\mapsto{\bf{Acceleration = {\cancel\frac{50 - 70}{0.5} }}}}$

${\blue{\dashrightarrow{\red{\boxed{\bf{-40km/h}}}}}}$

So,

${\red{\underline{\green{\boxed{\mathfrak{Acceleration = -40km/h}}}}}}$

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