Term 2 Chapter 3 Flashcards
What is work and what is the formula of work?
Work: Work is the use of force to move an object over a distance.
W = f*d (force * distance)
What is gravitational potential energy and what is the formula?
Gravitational potential energy: Potential energy/stored energy caused by gravity. GPE = mgh
What is the formula of mechanical energy?
Mechanical energy: KE + PE
What is power and what is the formula with the unit?
Power: Power is the rate at which you do work. Power is calculated in watt.
Power = work / time
What is a horsepower and what is the power of a horsepower?
One horsepower is the amount of work a horse can do in one minute.
1 horsepower = 746 watts of power.
What is the law of conservation of energy?
“Energy can neither be created or destroyed but can be transformed from one form to another.” The total amount of energy never changes as different forms of energy get involved in any process.
What is the relation between work and energy?
Both are measured in joules and energy is needed to do work.
How does a rack/pulley help you do work?
This machine helps to perform work by changing the direction of forces and making easier the moving of large objects.
The formula of efficiency and formula of mechanical advantage
Efficiency: Output Work / Input Work * 100
Mechanical advantage: output force / input force
What is a machine
A machine is any device that makes work easier.
What can a machine do?
A machine can:
- Increase the distance
- Increase the size of the force
- Change the direction of force
What is efficiency and how can you increase the efficiency of a machine?
The more efficient a machine is the closer it is to the ideal machine mechanical advantage. To increase the efficiency of a machine, lubricants like oil or grease can be used.
