Answer:
The velocity of the skateboard is 0.774 m/s.
Explanation:
Given that,
The spring constant of the spring, k = 3086 N/m
The spring is stretched 18 cm or 0.18 m
Mass of the student, m = 100 kg
Potential energy of the spring, 
To find,
The velocity of the car.
Solution,
It is a case of conservation of energy. The total energy of the system remains conserved. So,






v = 0.774 m/s
So, the velocity of the skateboard is 0.774 m/s.
821
s
s
s
s
s
s
s
s
s
s
s
s
ws
asd
asd
asd
asd
ad
a
sda
d
≥≡³
Answer:
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
Earth has its own atmosphere. That is one reason all the water that has been on Earth has been recycled through the water cycle. It never leaves Earth’s atmosphere.
When the parachute deploys it increases the persons air resistance to (temporaily) greater than the force of weight. This causes them to decellerate. As they decellerate resistance decreases again until once again it balances out. Terminal velocity is reduced to a safe level, and landing without injury is possible.