Escape velocity is the speed that an object needs to be traveling to break free of a planet or moon's gravity well and leave it without further propulsion. For example, a spacecraft leaving the surface of Earth needs to be going 7 miles per second, or nearly 25,000 miles per hour to leave without falling back to the surface or falling into orbit.
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.
The third option seems correct. Using any bag more than once will help in decreasing the carbon foot print.
This isds beause, if you use paper bag once only, then paper bag is being utilised and more and more paper is being used. So the best way is to use the bag more than once, whichever bag u are using.
Explanation:
For each object, the initial potential energy is converted to rotational energy and translational energy:
PE = RE + KE
mgh = ½ Iω² + ½ mv²
For the marble (a solid sphere), I = ⅖ mr².
For the basketball (a hollow sphere), I = ⅔ mr².
For the manhole cover (a solid cylinder), I = ½ mr².
For the wedding ring (a hollow cylinder), I = mr².
If we say k is the coefficient in each case:
mgh = ½ (kmr²) ω² + ½ mv²
For rolling without slipping, ωr = v:
mgh = ½ kmv² + ½ mv²
gh = ½ kv² + ½ v²
2gh = (k + 1) v²
v² = 2gh / (k + 1)
The smaller the value of k, the higher the velocity. Therefore:
marble > manhole cover > basketball > wedding ring
Answer:
The smallest radius will be four (4) times the initial radius
Explanation:
The car maintains a constant angular speed. According to Newton's Second Law F = m a
1. 
2. 
Replacing 2 in 1
3. 
Where:
Fr= Frictional force
Rp= Initial Radius
An= Centripetal Acceleration
M= Mass
V= Velocity
Also we have that:
4. 
μ= Coefficient of friction between the car and the surface
M= Mass
W= Weight
G= Gravity
r is cleared from equation 3
5. 
Replacing 4 in 5
6. 
Simplifying
7. 
Now we have a new velocity equal to twice the initial velocity, We replace it by 2v in equation 7
8. 
Computing
9. 
Replacing 5 in 9
