physics
posted by Tunde .
A boat is ravelling in a river with a current of 3 km/hr. The boat is capable of travelling at 10 km/hr in still water. How long will it take the boat to travel 7km upstream

The boat velocity relative to land, going upstream, is 10  3 = 7 km/h
Time to travel 7 km
= 7 km/(7 km/h)
= 1 hour
Respond to this Question
Similar Questions

Physics
A boat that can travel at 4.0 km/hr in still water crosses a river with a current of 1.8 km/h. at what angle must the boat be pointed upstream to travel straight across the river? 
physics
A boatâ€™s speed in still water is vBW = 1.85 m/s. If the boat is to travel directly across a river whose current has speed vWS = 1.20 m/s, at what upstream angle must the boat head? 
algebraNOW PLEASE
A boat is traveling in a river with a current that has a speed of 1.5 km/h. In one hour, the boat can travel twice the distance downstream as it can travel upstream. What is the boat's speed in still water? 
Physics
A boat must cross a 260mwide river and arrive at a point 110 upstream from where it starts. To do so, the pilot must head the boat at a 45 degree upstream angle. THe current has speed 2.3 m/s. a) What is the speed of the boat in … 
Physics
A boat sets off perpendicular to the bank, to cross a river width of 250m. The speed of the boat in still water is 3.20ms1, however there is a current downstream at 1.20ms1, which puss the boat sideways. a) Find the resultant velocity … 
physics
A boat must head due north across a river channel that has a current of 9 km/hr towards the west. The boat is capable of traveling at 28 km/hr in still water. If the boat heads into the current to keep its true north course, what will … 
Physics
a boat moves through the water of a river at 5.8m/s relative to the water, regardless the boat's direction. if the current is flowing at 5.04m/s, how long does it take the boat it take the boat to complete a trip consisting of a 443m … 
Math! Algebra 1!
A boat is traveling in a river with a current that has a speed of 1.5 km/h. In one hour, the boat can travel twice the distance downstream as it can travel upstream. How long will it take the boat to travel 100 km in still water? 
phy
5. A boat capable of making 9.0 km/hr in still water is travelling upstream in a river flowing at 4 km/h. An object lost overboard is not missed for 30 minutes. (a) If the boat is then turned around, how long will it take to overtake … 
Physics
A boat that can travel at 3.0 km/h in still water crosses a river with a current of 1.7 km/h. At what angle must the boat be pointed upstream to travel straight across the river?