Please write in English because I do not understand
Boyle's law states:
pV = C, where p = pressure, V = volume, C = constant.
Therefore,
p1V1 = p2V2
And the,
p2 = p1V1/V2
p1 = 512 kPa
V1 = 5l
p2 =?
V2 = 4l
Therefore,
p2= 512*5/4 = 640 kPa
Since the lemon is falling without any air resistance, the only force acting on the lemon is the acceleration due to gravity.
But, since we know that the lemon is falling with a constant speed. There has to be another unknown force to balance the gravitational force. Which has been shown in the freebody diagram
Two atoms with the same atomic number, but different mass numbers (same number of protons, different number of neutrons), are called isotopes, or isotopic nuclides. Having different numbers of neutrons changes the mass of these atoms, so isotopes have slight variations in their physical and chemical behavior.