Part A
Free fall motion
h = 3.1 m
Equation: Vf = √(2gh) = √(2*9.8 m/s^2 * 3.1 m) = 7.8 m/s
That is the only part in the question.
Answer:
Ro = 8.65 [g/cm³]
Explanation:
We must remember that density is defined as the ratio of mass to volume.

where:
m = mass = 0.450 [kg] = 450 [g]
V = volumen = 52 [cm³]
Ro = density [g/cm³]
Now replacing:
![Ro = 450/52\\Ro = 8.65 [g/cm^{3} ]](https://tex.z-dn.net/?f=Ro%20%3D%20450%2F52%5C%5CRo%20%3D%208.65%20%5Bg%2Fcm%5E%7B3%7D%20%5D)
Answer:
If a negatively charged balloon is brought near one end of the rod but not in direct contact, then <u>the negative charges on the balloon repel the same amount of negative charges on the end of the rod that is close to the balloon</u>, and the positive charges stay at the balloon-side of the rod. The total charge of the rod is still zero, but the distribution of the charges are now non-uniform.
If the distance around the equator is reduced by half, then the radius is also reduced by half.
Since the acceleration due to gravity is proportional to 1/(radius²),
the acceleration changes by a factor of 1/(1/2)² = 1/(1/4) = <em>4 </em>.
The acceleration due to gravity ... and also the weight of everything on Earth ...
becomes <em>4 times what it is now</em>.
Do you have a book about it? or if you have a dictionary?