幾題物理計算題(流體力學) 幫幫我

這幾題我不知如何下手 請幫幫我 1. Before beginning a long trip on a hot day, a driver inflates an automobile tire to a gauge pressure of 1.8 atm at 293K. At the end of the trip, the gauge pressure in the tire has increased to 2.1 atm. What volume of air(measured at atmospheric pressure) should be released from the tire so that... show more 這幾題我不知如何下手 請幫幫我

1. Before beginning a long trip on a hot day, a driver inflates an automobile tire to a gauge pressure of 1.8 atm at 293K. At the end of the trip, the gauge pressure in the tire has increased to 2.1 atm. What volume of air(measured at atmospheric pressure) should be released from the tire so that the pressure returns to its initial value?

2. A water tank open to the atomosphere at the top has two holes punched in its side, one above the other. The holes are 5cm and 12cm above the ground. What is the height of the water in the tank if the two streams of water hit the ground at the same place?

3. A small ball 0.6 times as dense as water is dropped from a height of 10m above the surface of a smooth lake. Determine the maximum depth to which the ball will sink. Disregard any energy transferred to the water during impact and sinking.

4. In testing a new material for shielding spacecraft, 150 ball bearings each moving at a supersonic speed of 400m/s collide head-on abd elastically with the material during a 1 min interval. If the ball bearings each have a mass of 8g and the area of the tested material is 0.75m^2, what is the pressure exerted on the material?


5. The pressure in a constant-volume gas thermometer is 7.09*10^5 pa at 100度C and 5.19*10^4 pa at 0度C. What is the temperature when the pressure is 4.05*10^3pa?

thank you
Update: 下禮拜一要考試 可以盡快幫我嗎 感激不盡
Update 2: 謝謝您的回覆! 剛剛我自己也解出第1和2題 我知道最後一題很奇怪= =
第一題因為題目寫是gauge pressure(我不知道中文名詞)所以還要加上大氣壓力1atm


3. 一個小球的密度為水的0.6倍,由10公尺高空中丟入湖中。計算小球下沉的最大深度。...

4. 在測試一種新的航空材料,有150個球在1分鐘以400公尺/秒碰撞此測試材料。一個... 2,請問此測試材料所受的壓力為何?21Pa
Update 3: 還有一題
5. 在1秒中有5*10^23個氮氣分子以300m/s的速度碰撞一道面積為8cm^2的... 18000Pa
Update 4: 我不知道我第4和5題錯在哪 這是同樣的題型

F=(mv)/t 所以我可以算出力然後再除以面積不就是壓力?
3 answers 3