September 24

AP physics

Exam retake…

October 1In:A 20 kg box is pushed 10 meters across a

floor with a coefficient of friction of .5 with a force of 3000 N?

How fast is it going at the end?

Objective:

What is work?

SC:

Be able to solve work problems

Types of Energy: Work

Work

Notes:

Work=force x distance Force and distance must be in the same

direction

Problem:

A windmill pumps 200 kg of water a distance of 10 meters high. How much work did it do?

Problem:

A boy picks up a 10 kg box 1 meter and carries it 20 meters to a shelf. The shelf is 2 meters high. After he puts it on the shelf, how much work did he do?

Problem:

The same boy picked up the same box 2 meters, carried it 10 meters across a room and the put it on the 2 meter shelf. How much work was done?

Problem:

The same boy picked up the same box 2 meters, carried it 40 meters across a room and then lowered it down and put it on a 1 meter shelf. How much work was done?

problem:

A 10 kg box is pushed up a ramp with a incline of 30o to a height of 10 meters. The distance up the ramp was 20 meters. What was the work done?

10 m20 m

problem:

A 10 kg box is picked up and set at the top the ramp, 10 meters high. What was the work done?

10 m20 m

Problem:

A suitcase is pushed at an angle of 30o from the horizontal with a force of 10 N for a distance of 30 meters. How much work was done?

Turn to your neighbor

Summarize what you have learned about work

Out:

An excavator picks up a 1000 kgpiece of conduit 5 meters high. How much work was done?