While driving on the freeway at 110km/h , you pass a truck whose total length you estimate at 25m .
a) If it takes you, in the driver’s seat, 5.3s to pass from the rear of the truck to its front, what is the truck’s speed relative to the road?
b) How far does the truck travel while you’re passing it?
a) If it takes you, in the driver’s seat, 5.3s to pass from the rear of the truck to its front, what is the truck’s speed relative to the road?
b) How far does the truck travel while you’re passing it?
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At 110kph., you take 5.3s. to gain a distance of 25m.
(110,000/3600s) = 30.555m/sec.
The truck is slower by (25/5.3) = 4.717m/sec.
a) Truck's speed = (30.555 - 4.717) = 25.838m/sec., which is (25.838 x 3600) = 93,016.8metres/hr., = 93kph. (rounded).
b) (4.717 x 5.3) = 250m. travelled by the truck while you pass.
(110,000/3600s) = 30.555m/sec.
The truck is slower by (25/5.3) = 4.717m/sec.
a) Truck's speed = (30.555 - 4.717) = 25.838m/sec., which is (25.838 x 3600) = 93,016.8metres/hr., = 93kph. (rounded).
b) (4.717 x 5.3) = 250m. travelled by the truck while you pass.