Conservation of Energy

Conservation of Energy: Law of Conservation of Energy and Mechanical Energy

By Stacy Polanco

Law of Conservation of Energy​

• Energy​ can never be created nor destroyed but can be transformed into other forms

MUST REMEMBER!!​

1. Energy cannot be destroyed

2. Energy cannot be created

3. ​Energy can ONLY be transformed from one form to a another

​The higher you swing the most potential energy, when you swing down it is transformed to kinetic energy

Riding the Swings​

Chemical Potential Energy from the gasoline transforms to kinetic energy when the car moves ​

Car Engine ​

Energy Being transformed from one form to an another ​

Multiple Choice

What is not a true statement about energy?

• Energy cannot be destroyed

• Energy is created in a form heat and mechanical energy

• Energy cannot be created

• Energy can only be transform from one form to another

Multiple Select

What are the types of energy? (Select the ones that apply)

• Elastic Energy

• Potential

  Energy

• Kinetic Energy

• Body Energy

The sum of the kinetic energy and potential energy is equal to mechanical energy​

ME= mechanical energy

KE= kinetic energy

PE= potential energy ​

​

ME= KE + PE

Energy= ​is the ability to change

Total energy of a closed system is a conserved, which mechanical energy​

Law of Conservation Energy ​

MECHANICAL ENERGY​

​Mechanical energy(total energy) remains the same even when it transforms from potential energy to kinetic energy.

Some text here about the topic of discussion

PE= m*g*h​

​

Remember: g= 9.8 m/s²​

Potential Energy Formula​

KE= 1/2mv²​

KINETIC ENERGY ​FORMULA

REMEBER FORUMLAS

​Mechanical Energy with Initial and Final Energy

​HINT: TAKE NOTES WHATS ABOVE

Multiple Choice

What is the formula of Mechanical Energy?

• 1/2mv^2

• m*g*h

• 2+3x

• 1/2mv^2 + m*g*h

Multiple Choice

What is the formula of KE?

• 1/2mv²

• m*g*h

• x+5x²

• 0.5*m*g*h

Multiple Choice

What is the formula for PE?

• 1/2mv²

• m*g*h

• 9.8 0.5g

• x+4x

Example: ​A 25.0 kg object falling towards earth has a velocity of 8.5 m/s when it is 100 m above ground. What will be it velocity when it is 20 m above ground?

Example: ​A 25.0 kg object falling towards earth has a velocity of 8.5 m/s when it is 100 m above ground. What will be it velocity when it is 20 m above ground?​

​Given:

m= 25 kg

v_i = 8.5 m/s v_f = ?

h_i = 100 m h_f = 20 m

​

v_f= 40.5 m/s​