Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 11-science Answered

Pls solve
question image
Asked by pb_ckt | 16 Jun, 2019, 09:36: PM
answered-by-expert Expert Answer
distance travelled = average velocity×time ...............(1)
 
average velocity = 72 km/hr = 20 m/s
 
distance travelled = 20×25 = 500 m .......................(2)
 
Let t be the time in seconds, car has travelled with uniform acceleration 5 m/s2
 
distance S1 travelled with uniform acceleration is obtained as,   S1 = (1/2)×at2 = (1/2)×5×t2   =  2.5 t2 m  ................(3)
 
velocity u after t seconds is given by,  u = a×t = 5×t m/s
 
distance S2 travelled before coming to rest if retardation is 5 m/s2 :-    S2 = u2/(2a) = 25t2 /(2×5) = 2.5 t2 .............(4)
 
Total distance S  travelled is obtained by adding eqn.(3) and eqn.(4)
 
 S = S1+S2  = 2.5t2 + 2.5t2 = 5 t2 = 500 m ..................(5) 
 
Hence by solving eqn.(5) for t,  we get  t = 10 s ;  Hence car has initially travelled 10 s with uniform acceleration .
Answered by Thiyagarajan K | 16 Jun, 2019, 10:30: PM
CBSE 11-science - Physics
Asked by sheikhsaadat24 | 17 Apr, 2024, 09:41: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 11-science - Physics
Asked by sumedhasingh238 | 29 Mar, 2024, 05:15: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 11-science - Physics
Asked by sumedhasingh238 | 28 Mar, 2024, 11:10: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 11-science - Physics
Asked by roshnibudhrani88 | 23 Mar, 2024, 05:52: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
Get Latest Study Material for Academic year 24-25 Click here
×