A car is traveling with a speed of 54 km/hr the driver applies the break and retards the car uniformly.the car is stopped in 5 seconds 1) The redardation of the car 2)Distance travelled before it is stopped after apply the break

Asked by rsaranya658 | 30th Jun, 2022, 02:44: PM

Expert Answer:

Initial speed = 54 km/hr = 54 × (5/18) = 15 m/s
 
Retardation a is determined from following equation
 
" v = u - ( a × t ) "
 
where v is final speed that is zero because after time t the car comes to rest. Initial speed is u
 
a = u / t = 15/5 = 3 m/s2
 
Distance S travelled is determined from the following equation
 
" S = ( u t ) - [ (1/2) a t2 ]  "
 
S = ( 15 × 5 ) - [ (1/2) × 3 × 5 × 5 ]
 
S = 37.5 m

Answered by Thiyagarajan K | 30th Jun, 2022, 03:02: PM