Answer:
Explanation:
Let the cross sectional area be a cm .
volume of hydrometer inside liquid = 12 x a = 12 a
weight of liquid displaced = 12a x .8 x g = 9.6 a g
For free floatation of liquid
weight of hydrometer = weight of displaced liquid
9.6 a g = 100 g
a = 10.41 cm²
cross sectional area = 10.41 cm².
When discussing Newton's laws of motion, particularly Newton's third law of motion, the terms that almost everyone will use are "action" and "reaction".
You must not take this to mean that they understand what they're talking about.
Answer: option (D.)They send signals in the gigahertz range to relays in the line of sight.
Explanation:
Microwaves are a form of electromagnetic waves with wavelengths between from about a meter to a millimeter; and they possess frequencies between 300 mega hertz(MHz )and 300 giga hertz(GHz.)
Microwaves travel by line-of-sight; unlike other radio waves of lower frequency. They do not bend around hills, nor follow the earth's surface as ground waves, nor reflect from the ionosphere .Therefore land microwave communication links are restricted only tovisual horizon to about 40 miles (64 km).
Speed must an electron have if its momentum is to be the same as that of an x-ray photon with a wavelength of 0. 85 nm is 8.6*10^5m/s.
To find the answer, we have to know about the energy of photon.
<h3>What is the speed of the electron here?</h3>
- As we know that the momentum of an x-ray photon with a wavelength w,
where; h is the plank's constant.
- Thus, the momentum will be,
- We have to find the speed of the electron, thus, we have the expression of linear momentum as,
Thus, we can conclude that, speed must an electron have if its momentum is to be the same as that of an x-ray photon with a wavelength of 0. 85 nm is 8.6*10^5m/s.
Learn more about the energy of photon here:
brainly.com/question/3584036
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