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Giraffe is the tallest animal on the earth at present, so its blood pressure is also the highest among the animals. The average height of an adult giraffe can reach 4.3m, its mass can reach 2T, and the landing area of one sole of a giraffe is 250cm2? (2) If the blood density of a giraffe is 1.05 × 103kg / m3, when its heart contracts, it is necessary to press the blood to the head 3M higher than the heart, then at least how much pressure should be produced when the giraffe's heart contracts? (systolic pressure refers to the pressure produced when the heart contracts. Atmospheric pressure is not taken into account in calculation. In this problem, G is taken as 10N / kg.)
(1) When giraffes stand, the pressure on the horizontal ground is f = g = mg = 2 × 103kg × 10N / kg = 2 × 104n, the pressure on the horizontal ground is p = FS = 2 × 104n4 × 250 × 10 − 4m2 = 2 × 105Pa; (2) the required pressure is at least p ′ = ρ GH = 1.05 × 103kg / m3 × 3M × 10N / kg = 3.15 × 104
What is the density of general block stone and granite stone
In general, when estimating the gross weight of granite:
The density of black granite is 3 tons / m3
Other colors are 2.7t/m3
How to estimate the density of granite?
Urgent, quick!
Take a small piece of granite, hold the granite with the left hand, and hold n eggs with the right hand. 50N (g) is the mass. When the side volume is estimated, the volume mass / volume of boiled water can be calculated
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