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2 miles per second upstream relative to the river bank.

Note: This is quite a scenario, even for experienced rapids-shooters.

That river is flowing at 28,800 miles per hour, and the guy is paddling

his kayak through the water at 36,000 miles per hour. The whole scene

is definitely poised to launch itself into solar orbit.

Q: If a river current is 8.0 miles per second and a boat is traveling 10.0 miles per second upstream what is the boat's speed relative to the riverbank?

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f a river current is 8.0 m/s, and a boat is traveling 10.0 m/s upstream, what is the boat's speed relative to the riverbank?

The current speed is about 4 miles per hour.

The current flows at 4 kph.The boat motors at 11 kph.

Call the unknown speed of the current c and the speed of the boat in still water b. When travelling upstream, the net speed of the boat will be b - c and when travelling downstream the net speed of the boat will be b + c. Since b = 4c, the speed upstream will be 3c. The distance upstream is one-half the total travelling distance of 150 km or 75 kilometers. Distance travelled = speed X time at speed, so that upstream time = 75/3c, downstream time = 75/5c, and the sum of these is the total time stated to be 8 hours. Thus 75/3c + 75/5c = 8. Multiplying both sides by 15c yields 75(5 +3) = 120c, or c = (8 X 75)/120 = 5 kilometers per hour.

The speed upstream is B - C where B is the speed of the badge in still water and C is speed of the current The speed downstream is B + C. Velocity = Distance/Time : therefore Time = Distance/Velocity. Time for upstream journey = 6/(B - C) Time for downstream journey = 6/(B + C) BUT Total time for journey = 2 = 6/(B - C) + 6/(B + C) = 12B/(B2 - C2) Therefore 2B2 - 2C2 = 12B : However, B = 8kph so substituting gives, 128 - 2C2 = 96 : 2C2 = 32 : C2 = 16 : C = 4 The speed of the current is 4kph.

Related questions

f a river current is 8.0 m/s, and a boat is traveling 10.0 m/s upstream, what is the boat's speed relative to the riverbank?

ans is = 10 - 8 = 2 m/s (upstream)

If the boat is moving upstream at the same speed as the current moving downstream, the boat will appear to be stationary relative to an observer on the shore. This is because the boat's upstream motion is being cancelled out by the downstream motion of the current.

In order to ferry a current you need to point your boat an an angle across the river and pointing upstream. The stronger the current the more you will have to point upstream. You simply paddle at this angle until you reach the other side. It also can help if you lift your upstream knee slightly so that the water doesn't catch your upstream edge.

The current speed is about 4 miles per hour.

Swimming upstream is to do something the hard way. It is more difficult to swim against the current. Salmon swim upstream in order to spawn.

if the boat turns toward the dock without going upstream, it will miss it's mark because the current is pushing the boat downstream.

The boat travels past the water around it at 15 mph.If the water is moving past the riverbank at 3 mph, then the boat is moving past the riverbankat (15 - 3) = 12 mph.At 12 mph, it takes (30/12) = 2-1/2 hours (2hr 30min) to travel 30 miles up the riverbank.Coming back, the boat's speed past the riverbank will be (15+3) = 18 mph.It will take (30/18) = 1-2/3 hours (1hr 40min) to travel 30 miles down the riverbank.

Yes, a floating leaf is in motion with respect to a stream because it moves along with the water current. The leaf may appear stationary relative to the surrounding water and riverbank, but it is actually traveling with the flow of the stream.

If the fault is a direct short to ground, the fault current can be high enough to trip the upstream protection.

Yes, an electric current traveling through a wire generates a magnetic field. There is no way that it cannot do this.

The velocity of the boat relative to the shore is the vector sum of its velocity relative to the river and the velocity of the river current. In this case, it would be 4 km/h (boat's speed) + 5 km/h (current's speed), which equals 9 km/h.