IB A3.4 - Boat Crossing River
Get the Formative assessment: FA03.4.docx
The Answers:
1-3: A boat points straight across a 68.0 m wide river and crosses it in 18.2 seconds. In doing this it is carried downstream 23.7 m
1. What the boat’s velocity with respect to the water? (3.74 m/s)
2. What is the speed of the current? (1.30 m/s)
3. What is the velocity (in angle magnitude notation) of the boat as it moves across the river? (3.96 m/s at an angle of 19.2o downstream of straight across)
4-5: A boat has a velocity of 3.72 m/s in a river with a current of 1.31 m/s. The river is 47.2 m wide.
4. If you point straight across the river, what time will it take you to cross? (12.7 s)
5. Where would you land if you pointed at an angle of 13.7o downstream of straight across?
(28.6 m downstream) (look at the middle example in the video flip where I point at a random angle)
The Instruction for this Unit:
The first example is basic:
