Rain is falling vertically with a speed of \(30\) m/s. A woman rides a bicycle with a speed of \(10\) m/s in the north to south direction. What is the direction in which she should hold her umbrella? [Given: \(\tan 16^{\circ}= 0.29, \& \tan 18^{\circ}= 0.33]\)
1. | \(16^{\circ}\) with the vertical, towards north |
2. | \(18^{\circ}\) with the vertical, towards north |
3. | \(16^{\circ}\) with the vertical, towards south |
4. | \(18^{\circ}\) with the vertical, towards south |
A man can swim at a speed of \(4.0\) km/h in still water. How long does he take to cross a river \(1.0\) km wide if the river flows steadily at \(3.0\) km/h and he makes his strokes normal to the river current?
1. \(20\) min
2. \(18\) min
3. \(15\) min
4. \(16\) min
In a harbor, the wind is blowing at the speed of \(72~\text{km/h}\), and the flag on the mast of a boat anchored in the harbor flutters along the \(\mathrm{N\text-E}\) direction. If the boat starts moving at a speed of \(51~\text{km/h}\) to the north, what is the direction of the flag on the mast of the boat?
1. | almost due north |
2. | almost due east |
3. | almost due west |
4. | almost due south |