Question

a car is moving in a straight line with the speed of 18 km per hour it is stopped in 5 seconds by applying brakes. find the retardation​

Answer 1

Answer:

u=18km/h=18*5/18=5m/s

v=0

t=5s

acceleration=0-5/5=-5/5=-1

retardation=1

Answer 2

ANSWER:

• Retardation = 1m/s²

GIVEN:

• Speed of car = 18 km/hr
• Time taken to stop the car after applying brake = 5 sec.

TO FIND:

• Retardation.

SOLUTION:

Changing 18 km/hr into m/s.

= 18000/3600

= 5 m/s

Here

Initial velocity (u) = 5m/s

Final velocity (v) = 0 m/s

Time = 5 sec

Formula:

=> Acceleration (a) = [FInal velocity (v) - Initial velocity (u)]/Time(t)

Putting the values we get;

=> a = 0-5/5

=> a = -5/5

=> a = -1 m/s²

Negative acceleration is called retardation.

Retardation = 1m/s²