Question

hi friends please answer this question it is very very urgent sorry friends subject is physics

Answer 1

Hey there !!!!

13) Car starts from rest so initial velocity "u" =0 

Final velocity (v) = 36kmph =36*5/18 = 10m/s  time =5 seconds.

   Now ,

                        v=u+at

                        10=0+a*5

                        a=2m/s²

Distance traveled:
 
                       v²-u²=2as

                       10²=2*2*s

                        100/4=s


                           s=25m.

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14)A body travels with initial velocity 36km/h =36*5/18 = 10m/s

u=10m/s   a=5m/s²  t=20s

         v=u+at

          v=10+5*20

          v=110m/s

Final velocity =110 m/s.

Distance traveled in 20 seconds is "s"

       s=ut+at²/2

u=10m/s t=20s a=5m/s²

 s= 10*20+5*(20)²/2

s=200+1000

s=1200m

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15) Car travels with a velocity 60m/s for 10s and comes to rest in next 5s

So total time of the journey = 15s.As car comes to rest final velocity (v)=0

 u=60m/s

                  v=u+at 
                   
                 0=60+15a

          -60=15a

          a=-4m/s² ( negative sign indicates retardation).

Distance traveled in 15s

                          s=ut+at²/2

  u=60m/s  t=15s  a=-4m/s²

  
                       s=60*15-(4*(15)²/2)
 
                       s=900-2*225
 
                       s=900-450 =450m

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Hope this helped you................