Answer: The atomic number is the number of protons in an atom, and isotopes have the same atomic number but differ in the number of neutrons. The number of protons in an atom is called its atomic number. This number is very important because it is unique for atoms of a given element. All atoms of an element have the same number of protons, and every element has a different number of protons in its atoms.
Explanation:
fraction equation is<span>
F =µR
F=friction,µ=coefficient , R=reaction = mg
use same equation for b part, but the reaction is no longer mg because the plain is now inclined. Draw a forces diagram and you will see that the reaction force can be calculated from the weight of the object and inclination of the plain using trigonometry.</span>
Answer: 500 Watts
Explanation:
Power 
is the speed with which work 
is done. Its unit is Watts (), being 
.
Power is mathematically expressed as:
(1)
Where 
is the time during which work is performed.
On the other hand, the Work done by a Force 
refers to the release of potential energy from a body that is moved by the application of that force to overcome a resistance along a path. It is a scalar magnitude, and its unit in the International System of Units is the Joule (like energy). Therefore, 1 Joule is the work done by a force of 1 Newton when moving an object, in the direction of the force, along 1 meter (
).
When the applied force is constant and the direction of the force and the direction of the movement are parallel, the equation to calculate it is:
(2)
In this case, we have the following data:
So, let's calculate the work done by Peter and then find how much power is involved:
From (2):
(3)
(4)
Substituting (4) in (1):
(5)
Finally:
I uploaded the answer to a file hosting. Here's link:
tinyurl.com/wpazsebu
