Answer:
The following options are true based on the properties of electric field;
a) Electric field lines near positive point charges radiate outward.
b) The electric force acting on a point charge is proportional to the magnitude of the point charge.
d) In a uniform electric field, the field lines are straight, parallel, and uniformly spaced.
Explanation:
From option b) From coulomb's law F = Kq1q2r/r2
Answer:
m = 4.65 kg
Explanation:
As we know that the mass of the water that evaporated out is given as

so the energy released in form of vapor is given as



now the heat required by remaining water to bring it from 15 degree to 100 degree



total heat required for above conversion

now by heat energy balance
heat given by granite = heat absorbed by water


Explanation:
time period= 1/frequency.
= 1/50 = 0.02 second.
hope this helps you.
Answer:
1) λ < 2d, 2) nfrared imaging technique, 3) each color there is a different index of refraction
Explanation:
We are going to answer the three questions
1) When x-rays pass through matter in order to be dispersed, their wavelength must be of the order of the length of separation in the atoms and molecules of the body, in solid bones this length is similar and they scatter and reflect the x-rays therefore they can be observed, the fat and the soft tissue have a much greater separation therefore the x-rays cannot be reflected and consequently it is not observable by this technique.
2) At airports they use the infrared imaging technique, where the image is taken for the infrared wavelength, which is the heat part of the electromagnetic spectrum; consequently, when the image is viewed, the hottest areas appear brighter and, since when a person has a virus, his temperature rises, his temperature rises, it is possible to observe people with a higher temperature.
3) when white light hits a prism it is refracted with the equation
n₁ sin θ₁ = n₂ sin θ₂
where the incidence of refraction depends on the wavelength, therefore for each color there is a different index of refraction and consequently the light is separated in its different colors.
FULL ANSWER
Neutrons and protons make up a nucleus and they are in the middle of an atom. Electrons surround the nucleus. Opposite charges attract each other. Because of this, protons do not attract other protons and electrons do not attract other electrons. Instead, protons attract electrons and electrons attract protons. When someone looks at the elements on the periodic table, they can see how many protons are present by looking at the atomic number. Since atoms have to have an equal amount of each, if an element contains 36 protons, it also has 36 electrons.