<span>The answer is physical change. This is a kind of change moving the form of a chemical substance, but not its chemical arrangement. Physical changes are used to isolate combinations into their constituent compounds, but cannot typically be used to distinct compounds into chemical elements or simpler compounds. When the salt dissolve in water it is a physical change. The chemical arrangement of the salt is not altered.</span>
Answer: Larmor suggested in 1919 that a self-exciting dynamo could explain the magnetic field of the earth, as well as that of the sun and other stars, but it was Elsasser and Bullard in the 1940s who showed how motion in the liquid core of the earth might produce a self-sustaining magnetic field. By this time seismology and other studies had given a clearer picture of the earth, as having a solid inner core, a liquid outer core, both with a composition more of metal (mainly iron) than rock, and a rocky mantle, all below a thin crust that is all we can directly see. Energy from radioactivity travels outwards as heat, producing thermal convection in the core. It seems that this convection is the cause of the earth's magnetic field, although our knowledge of the core and its dynamics is sketchy. Our knowledge is limited to saying that flow regimes like those that may be occurring in the core can produce self-sustaining dynamos, with characteristics similar to that needed to produce the earth’s magnetic field.
Explanation:
Answer:
0.0195 m
Explanation:
= density of hockey puck = 9.45 gcm⁻³ = 9450 kgm³
= diameter of hockey puck = 13 cm = 0.13 m
= height of hockey puck = 2.8 cm = 0.028 m
= density of mercury = 13.6 gcm⁻³ = 13600 kgm³
= depth of puck below surface of mercury
According to Archimedes principle, the weight of puck is balanced by the weight of mercury displaced by puck
Weight of mercury displaced = Weight of puck
I do not know
hi I thinks the answer is Tralse
Answer:
6.54 × 10⁻⁵ Pa-s
Explanation:
Since the shear force, F = μAu/y where μ = viscosity of fluid between plates, A = area of plates, u = velocity of fluid = 0.6 m/s and y = separation of plates = 0.02 mm = 2 × 10⁻⁵ m
Since F = μAu/y
F/A = μu/y where F/A = force per unit area
Since we are given force per unit area, F/A = 1.962 N per unit area = 1.962 N/m²
So, μ = F/A ÷ u/y
substituting the values of the variables into the equation, we have
μ = F/A ÷ u/y
μ = 1.962 N/m² ÷ 0.6 m/s/2 × 10⁻⁵ m
μ = 1.962 N/m² ÷ 0.3 × 10⁵ /s
μ = 6.54 × 10⁻⁵ Ns/m²
μ = 6.54 × 10⁻⁵ Pa-s
