Forces and Energy

What is Force?

The push or pull that causes an object to change it’s speed or direction of motion

What is Weight?

Just one example of a force; in this case, the force is due to gravity

What is a unit of a force?

It is called a newton, which is the force required to impart an acceleration of one meter per second squared to a mass of one kilogram

What is work?

An object when there is an applied force that is along the same line of movement

What is the Formula for work?

W=FD(Work=Force x Displacement)

What is a unit of work called?

A newton meter or joule

What does performing work do?

Use up energy, also measured in joules, which is equal to the amount of work performed

Why do we have to consume food regularly?

Because we are constantly using up energy: when we move, when our heart pumps blood, when our lungs inhale and exhale, when we generate warmth to maintain our body temperature, and so on

The nutritional information on food packages sometimes lists:

The food energy per serving in kilojoules in addition to the traditional British unit of kilocalories(usually referred to, confusingly, as “calories” in everyday speech)

What is power the rate of?

At which work is performed, or energy is converted

What is work defined as?

The amount of work done or energy converted per unit of time

What is one formula for power?

P=W/T(Power=Work/Time)

What is another formula for power?

Power=Force x Distance/Time (P=FD/T)

What is the main unit of power?

Watt

What is one watt defined as?

One joule per second