Traditional Culture Encyclopedia - Travel guide - During the National Day, Xiaowen go on road trip. When he passed the tunnel ahead, he wanted to measure the length of the tunnel, so he looked at his hand when he entered and exited the tunnel.

During the National Day, Xiaowen go on road trip. When he passed the tunnel ahead, he wanted to measure the length of the tunnel, so he looked at his hand when he entered and exited the tunnel.

Known: t =1:25-1:20 = 5min =112h, v = 40km/h.

Q: s=?

Solution: v = ST

∴ Tunnel length:

s = vt = 40k m/h× 1 12h≈3.3km

A: This tunnel is 3.3 kilometers long. ..