Kinetic Energy and Work

Notes

Kinetic Energy and Work Energy E ➢ is a scalar, it is directionless ➢ S.I. unit: joule, J Energy – Money analogy ➢ Money numbers are numbers associated with a family’s wealth ❑ A family is a system of people, each with various money accounts (bank accounts) ❑ Money numbers are measured in dollars $ ➢ Energy numbers are number associated with a system’s energy ❑ A system is a family of objects, each with various energy accounts ❑ Energy numbers are measured in joules J ➢ Money numbers ❑ can be transferred from one family member’s bank account to another family member’s account (e.g. checking account or savings account) ▪ e.g. from Grandma’s savings account to little sisters spending account ➢ Energy numbers ❑ can be transferred from one object’s energy “account” to another object’s energy “account” (e.g. kinetic energy account or potential energy account) ▪ e.g. from object A’s potential energy account to object B’s kinetic energy account ➢ Transaction ❑ the act of transferring money numbers between money accounts ➢ Work ❑ the act of transferring energy numbers between energy accounts 1 Ch 7 Kinetic Energy Kinetic Energy, K ➢ Energy associated with an object’s state of motion ❑ the...