A boat moves at 7.00m/s relative to the water. (You can neglect relativity at these slow speeds.)

The boat travels 100 m downstream and then 100 m upstream, returning to its original point. Find the time for the round trip

T = d/V = 200/7 = 28.57 s.

To find the time for the round trip of the boat, we need to consider the time it takes for the boat to travel downstream and the time it takes for the boat to travel upstream.

Let's first calculate the time it takes for the boat to travel downstream:
The speed of the boat relative to the water is given as 7.00 m/s. Since it is traveling downstream, we can add the speed of the river flow to this velocity.
Let's assume the speed of the river flow is v m/s. Therefore, the effective speed of the boat downstream would be (7.00 + v) m/s.

Using the formula: time = distance / speed
The distance the boat travels downstream is 100 m.
So, the time taken to travel downstream is t_downstream = 100 m / (7.00 + v) m/s.

Next, let's calculate the time it takes for the boat to travel upstream:
Since the boat is now traveling in the opposite direction, we need to subtract the speed of the river flow from the boat's velocity.
Therefore, the effective speed of the boat upstream would be (7.00 - v) m/s.

Using the formula: time = distance / speed
The distance the boat travels upstream is also 100 m.
So, the time taken to travel upstream is t_upstream = 100 m / (7.00 - v) m/s.

Now, to find the total time for the round trip, we add the time taken for the downstream journey and the time taken for the upstream journey:
t_round_trip = t_downstream + t_upstream

Substituting the values we obtained:
t_round_trip = 100 m / (7.00 + v) m/s + 100 m / (7.00 - v) m/s.

This equation gives us the time taken for the round trip of the boat, accounting for both the downstream and upstream journeys.