Answer:
-Reduce the mass of the earth to one-fourth its normal value.
-Reduce the mass of the sun to one-fourth its normal value.
-Reduce the mass of the earth to one-half its normal value and the mass of the sun to one-half its normal value.
Explanation:
The force (F) between two massive bodies (earth-sun system) is given by the following equation:
Where "g" is the gravitational constant "Me" is Earth's mass, "Ms" is the Sun's mass and "r" is the separation between the Earth and the Sun.
1-) If we reduce the mass of the earth to one-fourth its normal value:
2-) Reduce the mass of the sun to one-fourth its normal value.
3-) Reduce the mass of the earth to one-half its normal value and the mass of the sun to one-half its normal value.
4-) Increase the separation between the earth and the sun to four times its normal value.
.
Therefore, changes 1, 2 and 3 would reduce the magnitude of the force between them to one-fourth of the original value.
Answer:
F4.0
Explanation:
To obtain a shutter speed of 1/1000 s to avoid any blur motion the f-number should be changed to F4.0 because the light intensity goes up by a factor of 2 when the f-number is decreased by the square root of 2.
<span>The proton differs from the electron in sign although they have the same value. Like the electron, a proton will gain 215 electron-volts of eV in Kinetic energy. So 1.602Ă—10^-19 J * 215 = 344.43 * 10^(-19) J.
But K. E. = mv^2 / 2, so v^2 = 2 * K.E/m. The mass of a proton is 1.673 * 10^-27 kg. So v = âš(2 * 344.43 * 10^(-19))/1.673Ă—10^-27 = 688.86 * 10^(-19)/1.673Ă—10^(-27) = 411.75 * 10^(-19-(-27)) = âš411.75 * 10^(8) = 202196.56
Also for the electron we have v^2 = 2 * K.E/m but here mass, m, = 9.109 * 10^-31 kg. So we have v = âš(2 * 344.43 * 10^(-19)) / 9.109 * 10^-31 = 688.86 * 10^(-19)/ 9.109 * 10^-31 = 75.624 * 10^(-19 - (-31)) = 75.624 * 10^(21) and v = 2.749 * 10^11</span>
Answer:
A. chemical substance whose atoms all have the same number of protons
Explanation:
An element is a substance which contains identical atoms that have the same number of protons in the nucleus.
Elements are arranged in the periodic table according to their atomic number (= number of protons): so atoms of different elements have a different number of protons in their nuclei.
For a neutral atom, the number of electrons around the nucleus is also equal to the number of protons.
Moreover, atoms of the same element can have a different number of neutrons, despite having the same number of protons - these atoms are called isotopes.
