I need help with some horse questions, can you help me.

Need help with college physics!?

• I need help with the following questions. I'm not looking for just answers but also steps as to get to that answer (they don't have to be extremely detailed since I know providing diagrams would be hard but as much as can get the point across if you can!) so I can be able to apply this method for similar questions later. Thanks for any and all help! 1. A river is flowing a 2m/s East. A man can swim at 3m/s and is on the southern bank. the river is 300m wide. What is the fastest time the man can swim to the other bank? He chooses to angle his body at an angle W (unknown angle) N so that he will arrive at a point directly opposite. How long does it take him to reach the opposite bank? 2. A man is trapped down a well, depth 10m. He throws a stone (with a message attached) up, angled very slightly to the vertical, so the stone rises 2m above the ground and then falls back onto the ground. How fast was the stone thrown? how long was it in the air? 3. A hiker walks at a steady pace. she walks 5 km North and 3km N30(degrees)W. As the weather is turning bad she decides to walk straight back to camp. If it takes her 3 hours to get back how fast was she walking? How long did the whole hike take? 4. This is a think before you write question.Two horses are approaching on another on a straight tract running E-W. At t=0 the first horse is plodding along at 1km/h. The second horse is moving towards the first at 2km/hour. when they start out they are 1km apart. At t=0 a fly started off the nose of the first horse at 3km/h. When it reached the nose of the second horse it immediately turned around and retouched the first horse, and then turned again to approach the second horse, and so on until the horses met each other. A)how far had the first horse traveled when the fly touched the second horse for the first time? how far had the second horse gone at this point? what is the new distance between the horses, at this time? how far had the fly flown on this first leg? B)the fly repeats this game, buzzing between the horses until they meet. How far did the fly fly until he was smushed by the meeting noses?

• Answer:

  1. Imagine the necessary velocity parallel to the river for the man to cross it is 2 m/s without being carried away by the current. So that is one component of his velocity. Now you have 2 sides of a right triangle. There is one side that is 2 m/s running along the river, and one that is 3 m/s running diagonally. Use the Pythagorean Theorem to find side 3. Then figure out how long it will take based on the velocity that you found using the theorem. 2. Use the formula v= sqroot(2gh) , where h is the height, and g (9.8 m/s/s) is gravity. Hope this helps! 3. Draw a large triangle that shows what happened. Use trig to find the length the 3rd part of the triangle, and use x=vt to find the velocity. 4. I'm gonna be mean and let you figure this one out. Good luck!!