Question

A car starts from rest and accelerates one metre per second square find the distance travelled in 10 second​

Answer 1

Explanation:

For 0−5sec, 

a=4m/s2, Let velocity at 5sec is v and distance is S1

Using v=u+at   ⇒v=0+4×5=20m/s

Using s=ut+21at2  ⇒S1=0+21×4×52=50m

For next 25sec

v=20m/s  

⇒S2=20×25=500m

For comes to rest, 

u=20m/s , a=−2m/s2 

Using v2=u2+2as   ⇒0=202−2×2×S3

⇒S3=100m

Total distance =S1+S2+S3=50+500+100=650m

Answer 2

Answer:

V=at

⇒8=a10

⇒a=0.8m/s

2

V

2

=U

2

+2as

⇒U=8

2

+2×a64

⇒a=

2×64

−64

=−0.5m/s

2

Distance travelled= Area of graph

⇒584=

2

1

×10×8+8×t

1

+

2

1

×16×8

⇒584=40+8t

1

+64

⇒8t

1

=480

⇒t

1

=60

Total time= 10+60+16=86s