Answer:
Part a)

Part b)

Explanation:
As we know that the see saw bar is massless so here torque due to two masses is given as

here we will have

now we will have inertia of two masses given as

now we have

now the angular acceleration is given as

so we have

Part b)
Now if the rod is not massles then we will have total inertia given as

so we will have

now the acceleration is given as


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.
Answer:
High energy waves have high amplitudes
Explanation:
The sound is perceived as louder if the amplitude increases, and softer if the amplitude decreases. ... The amplitude of a wave is related to the amount of energy it carries. A high amplitude wave carries a large amount of energy; a low amplitude wave carries a small amount of energy