and

Work and Power

WORK WORK DISTANCE FORCE Work is defined as the product of the applied force and the displacement through which that force is exerted. W=F x d W=F(cosθ)d

Remember… 9.8 m/s2 F= m x a !!!

Try These... How much work is done lifting a 3N cabbage 2 meters into the air? 6 N·m (or joules) How much work is done by holding it there for 5 seconds? none (why?)

*NOTE Work is only done on an object when it is moved (displaced). In addition, work is only done when the object is moved in the direction of the force. Though work must be done on your muscles to hold it there, we are talking about work done on the object.

POWER Power is defined as work done divided by the time used to do the work. P = F(cosθ)d t P = F x d t

The SI unit for power is the joule/sec (or watt). A machine is capable of a power output of 1,000 watts. How far can it lift a 50N weight in 3 seconds? Problem HINT: Solve formula for “d” = 60 meters

putting it all together... How much work is done holding a 1,200 N piano at shoulder height for 15 minutes (your shoulder is 1.5m above the ground)? NONE What if we lifted the piano 1m over that time? 1,200 J How much power was exerted? 1.3 Watts

and

and

Presentation Transcript

Price and Output and

and

and

AND

And

Impulse and Momentum and Collisions and Stuff

maggie and milly and molly and may

Adult and on and on and on and on and on

maggie and milly and molly and may

“ maggie and milly and molly and may”

and

and

and

and

and

AND

AND

Latin (and Greek and English and . . . )

and

AND, OR and NOT

and