Answer:
The energy of an electron in an isolated atom depends on b. n only.
Explanation:
The quantum number n, known as the principal quantum number represents the relative overall energy of each orbital.
The sets of orbitals with the same n value are often referred to as an electron shell, in an isolated atom all electrons in a subshell have exactly the same level of energy.
The principal quantum number comes from the solution of the Schrödinger wave equation, which describes energy in eigenstates
, and for the case of an hydrogen atom we have:

Thus for each value of n we can describe the orbital and the energy corresponding to each electron on such orbital.
<u>Answer</u>
To increase friction for a better grip.
<u>Answer</u>
Most human beings do sweat hands especially on the palm. When this happens the person will not have a good grip of heavy objects because they will slide/slip from the hand.
<em>By applying the powder, you are trying to make the hand dry hence increasing the friction for a better grip. </em>
If the gymnast doesn't do this the parallel bars may slip from the hands and injure himself or herself.
Answer:
where L is the length of the ramp
Explanation:
Let L (m) be the length of the ramp, and g = 9.81 m/s2 be the gravitational acceleration acting downward. This g vector can be split into 2 components: parallel and perpendicular to the ramp.
The parallel component would have a magnitude of

We can use the following equation of motion to find out the final velocity of the book after sliding L m:

where v m/s is the final velocity,
= 0m/s is the initial velocity when it starts from rest, a = 2.87 m/s2 is the acceleration, and
is the distance traveled:

