For tests using a ballistocardiograph, a patient lies on ahorizontal platform that is supported on jets of air. Because ofthe ai
1 answer:
Answer:
v ’= - 1.76 10⁻⁴ m / s
Explanation:
We can solve this problem using momentum conservation. Defined a system formed by the patient, his blood and the platform in such a way that the forces are internal and the moment is conserved
initial instnate. Before pumping
p₀ = 0
final instant. Right after the heart pumping
p_f = m v + M v'
where m is the mass of blood and M the mass of the patient + the platform
p₀ = p_f
0 = m v + M v’
v ’= -
let's calculate
v ’= - 0.30
v ’= - 1.76 10⁻⁴ m / s
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A)
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The density of the droplet is
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B)
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and the distance between the plates is
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C) Surplus of 9 electrons
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we can think this charge has made of N excess electrons, so the net charge is given by
where
is the charge of each electron
Re-arranging the equation for N, we find:
so, a surplus of 9 electrons.