Ten questions. The result tells you which lessons you may skip.
The velocity of a body A relative to a body B is
A moves east at \(6\,\text{m/s}\) and B moves north at \(8\,\text{m/s}\). The speed of A relative to B is
Two bodies move with constant velocities in different directions. Seen from B, the body A moves along
A river \(60\,\text{m}\) wide flows at \(2\,\text{m/s}\). A boat moves at \(3\,\text{m/s}\) relative to the water and points straight across. The crossing takes
To land exactly opposite its starting point, a boat must point upstream of straight across at an angle \(\alpha\) with
A river flows at \(5\,\text{m/s}\) and a boat moves at \(3\,\text{m/s}\) through the water. Can the boat land exactly opposite its starting point?
Rain falls vertically at \(8\,\text{m/s}\). A person runs at \(6\,\text{m/s}\). To stay dry, the umbrella should be tilted
A man walking east at \(4\,\text{km/h}\) finds the rain falling vertically on him. The rain relative to the ground
An aeroplane with airspeed \(250\,\text{km/h}\) flies a straight course at right angles to a wind of \(150\,\text{km/h}\). Its ground speed along the course is
Two bodies move with constant velocities. The least distance between them is