At a distance L=400m from the traff...
Question
At a distance L=400m from the traffic light, brakes are applied to a locomotive moving at a velocity v=54km/hr. Determine the position of the locomotive relative to
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At a distance ( L=400 mathrm{m} ) from the traffic light, brakes are applied to a locomotive moving at a velocity ( v=54 mathrm{km} / mathrm{hr} . ) Determine the position of the locomotive relative to the traffic light 1 minute after the application of the brakes if its acceleration is ( -0.3 mathrm{m} / mathrm{sec}^{2} ).

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At a distance L=400m from the traffic light, brakes are applied to a locomotive moving at a velocity v=54km/hr. Determine the position of the locomotive relative to the traffic light 1 minute after the application of the brakes if its acceleration is −0.3m/sec^2.
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( u=54 times frac{5}{18}=15 mathrm{m} / mathrm{s} )
( a=-0.3 mathrm{m} / mathrm{s}^{2} )
( therefore quad v=u+a t )
( 0=15-0.3 mathrm{t}_{0} )
( t_{0}=frac{15}{0.3}=50 mathrm{sec} )
After 50 second, locomotive comes in rest permanently. ( therefore quad v^{2}=u^{2}+2 a s )
[
begin{array}{l}
mathrm{O}^{2}=15^{2}-2 times 0.3 mathrm{S}_{0}
mathrm{S}_{0}=frac{225}{0.6}=frac{2250}{6}=375 mathrm{m}
end{array}
]
the distance of the locomotive from traffic light ( =400-375=25 cdot mathrm{metre} )

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