Question

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Answer 1

d₁+d₂+d₃=d

d₁=d₃=d/4=100/4=25 m

d₂=d-2d₁=100-2*25=50 m

v₁²=v₀²+2ad₁<=>10²=0²+2a*25<=>100=50a=>a=100/50=2 m/s²

v₁=v₀+at₁<=>10=2t₁=>t₁=10/2=5 s

d₂=v₁t₂=>t₂=d₂/v₁=50/10=5 s

d₃=v₁t₃+at₃²/2<=>25=10t₃+2t₃²/2<=>t₃²+10t₃-25=0

Δ=100+100=200

t₃=(-10±10√2)/2=-5±5√2

t₃=-5+5√2=5(√2-1) s

t=t₁+t₂+t₃=5+5+5(√2-1)=10+5√2-5=5√2+5=5(√2+1) s

t=5(√2+1) s