A car moving along a straight highway with speed of 126 km/h is brought to a stop with a in a distance of 200 m.what is the retardation of the car

Question

Answer

Initial velo. (u) = 126×1000/3600 = 35m/s
displacement=s=200m
finally stops= v=0
v²-u²=2as
0-35²=2a×200
-35×35/(20×2)=a
a=-30.625m/s²

as in the ques. retardation is asking therefore the ans. will be 30.625m/s²

Answer

Retardation of car is -3.06meter per sec squre.. I calculate it by using the eq v^2 = u^2 +2as...

Answer

Given data:
Initial speed of the car (u) = 126 km/h
Final speed of the car (v) = 0 km/h (since it is brought to a stop)
Distance covered (s) = 200 m

To find the retardation of the car, we can use the equation of motion:

v^2 = u^2 + 2as

Where:
v = final speed of the car
u = initial speed of the car
a = retardation
s = distance covered

Converting units:
To ensure the units are consistent, we need to convert the speed from km/h to m/s as follows:

Initial speed (u) = 126 km/h * (1000 m/1 km) * (1 h/3600 s)
= 35 m/s

Final speed (v) = 0 km/h * (1000 m/1 km) * (1 h/3600 s)
= 0 m/s

Calculating retardation:
Using the equation of motion, we can rearrange it to solve for retardation (a):

v^2 = u^2 + 2as

0^2 = (35 m/s)^2 + 2a(200 m)

0 = 1225 m^2/s^2 + 400a

-1225 m^2/s^2 = 400a

a = -1225 m^2/s^2 / 400
a = -3.0625 m/s^2

Interpretation of the result:
The negative sign indicates that the retardation is in the opposite direction of the initial motion of the car. It is decelerating or slowing down.

Explanation:
The retardation of the car is found to be -3.0625 m/s^2. This means that for every second the car is in motion, its speed decreases by 3.0625 m/s.

The negative sign indicates that the car is decelerating or slowing down. If the retardation were positive, it would mean that the car is accelerating or speeding up.

The distance covered by the car is 200 m, and it comes to a stop from an initial speed of 35 m/s. This means that the car experiences a significant deceleration over the distance of 200 m, resulting in a final speed of 0 m/s.

The magnitude of the retardation can be used to analyze the car's braking system and the force applied to bring it to a stop. A higher magnitude of retardation would indicate a stronger braking force or a more efficient braking system.

Answer

55

Answer

v^2 - u^2 = 2a.s , 126*5/18 = 2a*200

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