Answer :
- Initial velocity=u=12m/s
- Final velocity=v=20m/s
- Time=t=45s
[tex]\\ \rm\hookrightarrow Acceleration=\dfrac{v-u}{t}[/tex]
[tex]\\ \rm\hookrightarrow Acceleration=\dfrac{20-12}{45}[/tex]
[tex]\\ \rm\hookrightarrow Acceleration=\dfrac{8}{45}[/tex]
[tex]\\ \rm\hookrightarrow Acceleration=0.1m/s^2[/tex]
Now
- Distance=s
[tex]\\ \rm\hookrightarrow v^2-u^2=2as[/tex]
[tex]\\ \rm\hookrightarrow (20)^2-12^2=2(0.1)s[/tex]
[tex]\\ \rm\hookrightarrow 400-144=0.2s[/tex]
[tex]\\ \rm\hookrightarrow 256=0.2s[/tex]
[tex]\\ \rm\hookrightarrow s=\dfrac{256}{0.2}[/tex]
[tex]\\ \rm\hookrightarrow s=1280m[/tex]