Solution :
Energy of photon, E = 6.7 eV
E =
joule
Kinetic energy, 


Kinetic energy at high speeds


r - 1 = 7130
r = 7130 + 1
r = 7131


![$v^2=C^2\left[1-\left(\frac{1}{7131}\right)^2\right]$](https://tex.z-dn.net/?f=%24v%5E2%3DC%5E2%5Cleft%5B1-%5Cleft%28%5Cfrac%7B1%7D%7B7131%7D%5Cright%29%5E2%5Cright%5D%24)

Δ = 1 - 0.99999999017
= 0.00000000933
Relative mass, 

kg
Answer:
In a closed system, the total energy is conserved or remains the same as energy transformations take place.
Explanation:
The law of conservation of energy states that energy cannot be created or destroyed but can be transformed from one form to another.
This law of conservation of energy applies only to a closed system. A closed system is a system which does not exchange energy with its surroundings. All forms of energy conversions occurring within a closed system does not result in an increase or decrease of the total energy of the system, rather, energy remains constant. For example, the universe is a closed system in that all forms of energy conversions occurs within it and energy is not exchanged with an external environment. However, the earth is not a closed system as some of the energy it receives from the sun can be radiated out into space. Since it's an open system, its total energy can change.
Answer:
Rolling friction is much smaller than sliding friction because Rolling friction is considerably less than sliding friction as there is no work done against the body that is rolling by the force of friction. For a body to start rolling a small amount of friction is required at the point where it rests on the other surface, else it would slide instead of roll.
Rolling Friction example: Anything with weels (cars,skateboards) or a ball rooling.
Sliding Friction example: Bicycle brakes,skinning your knee walking,writing.
Work with your units:
1 watt-hour = 1 (joule/second) · (hour) = 1 (joule-hour / second)
(1 joule-hour/sec) · (3600 sec/hour) = 3600 joules
So 1 watt-hour = 3,600 joules
Answer:
![r_{cm}=[12.73,12.73]cm](https://tex.z-dn.net/?f=r_%7Bcm%7D%3D%5B12.73%2C12.73%5Dcm)
Explanation:
The general equation to calculate the center of mass is:

Any differential of mass can be calculated as:
Where "a" is the radius of the circle and λ is the linear density of the wire.
The linear density is given by:

So, the differential of mass is:


Now we proceed to calculate X and Y coordinates of the center of mass separately:


Solving both integrals, we get:


Therefore, the position of the center of mass is:
![r_{cm}=[12.73,12.73]cm](https://tex.z-dn.net/?f=r_%7Bcm%7D%3D%5B12.73%2C12.73%5Dcm)