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Calculation of atmospheric pressure For a pressure cooker with a diameter of 20cm, the cross section of the vent is 10mm ^ 2. If the maximum pressure of steam in the cooker is 1.7 * 10 ^ 5pa, what is the mass of the pressure limiting valve? (set the external pressure as 1 * 10 ^ 5pa)
According to Pascal's principle, the pressure of the vent is 170000pa
According to f = PS
Exhaust pressure f = 170000 * 0.00001m ＾ 2 = 1.7n
That is, the gravity of the pressure limiting valve is 1.7n
m＝G／g＝1.7N．10N／kg＝0.17kg
A pressure calculation problem. Urgent
Xiao Ming weighs 600N, and the contact area between each shoe and his horizontal ground is about 200 square centimeters. What is the pressure on the ground at this time?
To be complete, it's the feet
Known: g = 600N, s = 200cm2
200 sq cm = 0.02 sq m
It has two feet
S (contact area) = 0.02 M2 × 2 = 0.04 M2
According to the formula: P = f / S = 600N / 0.04m2 = 15000pa
A: Xiaoming's pressure on the ground is 15000pa
By the way, make an advertisement: I'll take the high school entrance exam next Saturday and Sunday, remember to cheer me on
And... Little red flag
On the calculation of pressure and pressure
The area of the pin tip is 0.1 square mm, and the area of the nail cap is 1.5 square cm. When a force of 20n is applied to the nail cap, what is the pressure and pressure of the pin on the wall?
It's a process
The stress analysis shows that the pressure at the top of the graph is 20n, which has nothing to do with the thumbtack. The pressure is the ratio of the pressure to the stressed area
There is a 5000n cement board with a bottom area of 2M2 on the horizontal ground of a construction site. The crane lifts it to a height of 4m in 10s. Question: (1) when the cement board is placed on the ground, what is the pressure on the ground? (2) What is the work done by the crane to lift the cement board and the power of the crane?
(1) When the cement board is placed on the ground, the pressure on the ground: F = g = 5000n, the pressure on the ground: P = FS = 5000n2m2 = 2500pa; (2) the work done by the crane to lift the cement board: w = GH = 5000n × 4m = 2 × 104j, power: P = wt = 2 × 104j10s = 2000W The power of the crane is 2000 W
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