Introduction he problems on boat and stream is purely based on how accurately you are able to handle the =. Here you would have to take a special care of speed as there are four different types of speeds which you could encounter in the question; these are: 1. he speed of the boat in still water (he speed when the boat actually rows in pond).. he peed of the same in a river 3. he peed of the same in a river 4. he speed of the stream of the river What you would have to do is to bifurcate these four speeds in the questions and then apply it in our usual relation of =. Let us bifurcate it with the following discussion. iscussion: BOA & REAM 1. In a stream/river/water; he direction along the stream is called downstream. he direction against the stream is called upstream.. If the speed of a boat in still water is x km/hr and the speed of the stream is y km/hr; then:
peed of the (Along the ) = (x + y) km/hr peed of the (Against the ) = (x y) km/hr From the figure; we have; u = x + y v = x y By olving we have; he peed of the boat in still water;
x = u+v And the speed of thee stream; u v y = IMPORAN QUEION 1. A boat can travel with a speed of 13 km/hr. in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream. 68km 13 4 68km t 4hrs. 17km / hrs. t. A man's speed with the current is 15 km/hr. and the speed of the current is.5 km/hr. Find the man's speed against the current. ownstraem 15.5km / hr 10km / hr 3. A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same
distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively? 8 hrs 11 6 16 : 11 48 60 4 4 8 5 5 11 8:3 5 5 4hrs 4. A motorboat, whose speed in 15 km/hr. in still water goes 30 km downstream and comes back in a total of 4 hours 30 minutes. Find the speed of the stream (in km/hr.).
30km 15 15 tream tream 5km / hr otal 30km otal tream 1 4 hrs. 5. In one hour, a boat goes 11 km/hr. along the stream and 5 km/hr against the stream. Find the speed of the boat in still water (in km/hr.). tillwater tillwater tillwater 11 5km/hr 8km/hr ownstraem 6. A boat running downstream covers a distance of 16 km in hours while for covering the same distance upstream, it takes 4 hours. What is the speed of the boat in still water?
7. he speed of a boat in still water in 15 km/hr. and the rate of current is 3 km/hr. Find the distance travelled downstream in 1 minutes. tream 1 15 3km / hr hrs. 60 3.6km 8. A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, find the speed of the stream.
36 miles 10 miles/ hr till tream tream till tream miles/ hrs. ifference ifference tream ifference 36 miles 10 miles/ hr tream 90 hrs. 60 9. A man can row at 5 km/h in still water. If the velocity of current is 1 km/h and it takes him 1 hour to row to a place and come back, how far is the place? till tream till otal otal tream otal d d 5 km/ hr 1km/ hr 5 km/ hr 1km/ hr d.4 km 1hrs. 10. A boat covers a certain distance downstream in 1 hour, while it comes back in 1 1 hours. If the speed of the stream be 3 kmph, what is the speed of the boat in still water?
hr km till till till tream till tream till Uptream / 15 3 3 1 3
NOE