Magnetic force obeys an inverse square law with distance. ... If the distance between two magnets is halved the magnetic force between them will increase to four times the initial value.
If you heat that air by 100 degrees F, it weighs about 7 grams less. Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams. That's not much, and this is why hot air balloons are so huge -- to lift 1,000 pounds, you need about 65,000 cubic feet of hot air.
Answer:
B
Explanation:
F = ma , a = F/m
a1 = F/10 and a2 = F/4
Since Force is constant, a2 will we greater than a1
Answer:
In a positive ion, the number of protons is larger than the number of electrons.
In a negative ion, the number of protons is smaller than the number of electrons.
Explanation:
Each proton carries a positive charge of one unit.
Each elec in tron carries a negative charge of one unit.
In an atom, there are as many protons as electrons. Hence, they are neutral.
However, in a positive ion, there are less negative charge than positive charge. Hence the net charge is positive. That also means that there are fewer negatively-charged electrons than positively-charged protons.
Similarly, in a negative ion, there are more negative charge than positive charge. Hence the net charge is negative. That also means that there are more negatively-charged electrons than positively-charged protons.
