A: The positive charge if the protons in the nucleus equals the negative charge in the electron cloud.
Protons are positive, electrons are negative, and neutrons have no charge/are neutral
The third hour was positive acceleration and the second hour was negative acceleration
Answer:

Explanation:
As we projected the balloon at speed vo at an angle of 29 degree
so the two component of velocity is given as


now we know that in x direction we have



in y direction we have



now we have

Answer:
This question is incomplete but the completed question is below
As a girl pushes an object across a wood floor, she suddenly comes to an area where the floor has been waxed recently, making it slippery. What becomes true of the coefficient of kinetic friction? A. The coefficient of kinetic friction increases. B. The coefficient of kinetic friction decreases. C. The coefficient of kinetic friction becomes zero. D. The coefficient of kinetic friction becomes negative.
The correct option is B
Explanation:
Coefficient of kinetic friction can be defined as the frictional force resisted by the motion of an object. From the question, it might take the girl to apply a force equivalent to just half that of the weight of the object to overcome friction to keep the object moving on a wood floor. Once she gets to the waxed area, the frictional force reduces, thereby also reducing the coefficient of kinetic friction further. Thus, she will be able to use less than half of the force (equivalent to less than half of the weight of the object) to push the object.
Thus, the correct option is B.