Question

一列隊(duì)伍長(zhǎng)50m，以2.5m/s的速度通過(guò)一座全長(zhǎng)100m的橋，要多長(zhǎng)時(shí)間？

Answer 1

已知：隊(duì)伍長(zhǎng)s₁=50m，橋長(zhǎng)s₂=100m，速度v=2.5m/s
求：通過(guò)橋的時(shí)間t=？
隊(duì)伍通過(guò)的路程s=s₁+s₂=50m+100m=150m，
∵v=

s

t

，
∴隊(duì)伍通過(guò)大橋的時(shí)間：
t=

s

v

=

150m

2.5m/s

=60s．
答：隊(duì)伍過(guò)橋需要60s的時(shí)間．