Question

a car is travelling with uniform speed 54 km per h .by applying brakes it is brought to rest in 15 s . find the retardation​

Answer 1

Question:-

• A car is travelling with uniform speed 54 kmph by applying brakes it is brought to rest in 15sec . Find the retardation.

To Find:-

• Find the retardation of the car.

Solution:-

Given ,

• Car is travelling with uniform speed of 54 km/h.

• It applies brakes and comes to rest in 15 seconds.

Now ,

We have to find the deceleration of the car:-

$\sf\dashrightarrow \: v = u + at$

$\sf\dashrightarrow \: 0 = 15 + 15a$

$\sf\dashrightarrow \: 15a = - 15$

$\sf\dashrightarrow \: a = - \cancel\dfrac { 15 } { 15 }$

$\sf\dashrightarrow \: a = - 1 \:{ m/s }^{ 2 }$

Hence ,

• Retardation is -1 m/s²

Answer 2

Initial speed (u) = 15m/s

Final speed (v) = 0m/s

Time (t) = 15s

• To find, accelaration.
• a = v-u/t
• a = 0- 15/15
• a = -1m/s^2

$retardation \: = 1m \: \: {s}^{ - 2}$