Question

экскурсионный теплоход проходит по течению реки и после стоянкт возвращется в исходный пункт.найдите собственную скорость теплохода,если он прошел 120 км,скорость течения реки 4 км/ч,стоянка длилась 2 часа,а в пункт отплытия он вернулся через 10 часов

Answer 1

2часа+10часов= 12часов

120:12=10

10*4=40км/ч

Answer 2

Calculation of the Cruise Ship's Speed

To find the cruise ship's speed, we need to consider the distance it traveled, the duration of the journey, and the speed of the river's current.

Given information: - Distance traveled by the cruise ship: 120 km - Speed of the river's current: 4 km/h - Duration of the journey: 10 hours (including a 2-hour stop)

To calculate the cruise ship's speed, we can use the formula:

Speed = Distance / Time

However, we need to account for the effect of the river's current on the ship's speed. Since the ship is traveling upstream and downstream, the current will affect its speed differently in each direction.

Let's break down the journey into two parts:

1. Upstream journey (against the current): - Speed of the ship relative to the water: S - 4 (where S is the ship's speed) - Time taken for the upstream journey: 10 hours - 2 hours (stop) = 8 hours - Distance traveled upstream: 120 km

2. Downstream journey (with the current): - Speed of the ship relative to the water: S + 4 - Time taken for the downstream journey: 2 hours (stop) - Distance traveled downstream: 120 km

Now, let's calculate the ship's speed using the given information:

1. Upstream journey: - Distance = 120 km - Time = 8 hours - Speed = Distance / Time = 120 km / 8 hours = 15 km/h

2. Downstream journey: - Distance = 120 km - Time = 2 hours - Speed = Distance / Time = 120 km / 2 hours = 60 km/h

Since the ship's speed is different in each direction, we can take the average of the upstream and downstream speeds to find the cruise ship's speed:

Cruise Ship's Speed = (Upstream Speed + Downstream Speed) / 2 = (15 km/h + 60 km/h) / 2 = 37.5 km/h

Therefore, the cruise ship's speed is 37.5 km/h.

Please note that the above calculation assumes a constant speed throughout the journey and does not account for other factors that may affect the ship's speed, such as wind or waves.