# Physics

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A small boat is crossing a river which flows at 10km.h. The driver of the boat keeps it heading directly (at 90) away from the bank at a speed of 24 km/h relative to the water. The river is 0.5 km wide.

I calculated the speed of the boat relative to land - 26km/h
I calculated the direction the boat is actually traveling - 67* from bank
I calculated the time to get to the opposite bank - 1.25min

How far downstream will the boat drift before reaching the opposite bank?

How do I calculate that. ^

• Physics -

Yes, 5, 12 13 is a right triangle like 345 so you know without your calculator that 10^2 + 24^2 = 26^2

tan A = 10/24
so
A = 22.6 from straight across so 67.4 from the bank

time = .5/24 = .02083 hr = 1.25 min.

speed downstream = 10 km/hr
time under way = .02083 hr
distance = .2083 km

• Physics -

Can you help me with this question, too?

Suppose that the boat is supposed to arrive at a point directly across the river from its starting point.

a) What should be the heading of the boat?