Speed
The rate at which an object moves a certain distance.
Speed
What is the definition of work?
A force must be applied to an object and that object must move in the same direction as the force.
What is a simple machine?
A device for changing the amount and/or the direction of force to move an object.
Calculate the average speed of a boat that travels 600 meters in 40 seconds.
600/40= 15 m/s
When a box is moved up a ramp into a truck, the amount of work done depends on what?
The distance the box travels from the ground to the truck
A change in speed or velocity over a specific amount of time
Acceleration
The unit of measurement for work?
Joules
How does an incline plane make work easier?
By using an incline plane to increase the distance, less force is needed to do the work.
Jane and her mother take a road trip from Houston, TX to San Francisco, CA. It takes them 25 hours to make the 1400 mile trip.
What was their velocity?
1400 mi / 25 hr = 56 mph west
What is a fulcrum?
The point at which the rod pivots on a lever.
Speed in a given direction
Velocity
Which would be considered work?
Lifting a large box or carrying groceries to the car.
Lifting a large box.
A wedge
The speed of a jogger that ran 321 meters in 70 seconds.
4.6 m/s
Jessica is pushing a heavy box across the floor to clean her garage. She exerts a force of 20 N to move the box. After doing work on the box, she notices that she has applied a total of 80 Joules of work.
How far did Jessica move the box?
4 meters
What two pieces of information must you have in order to calculate the average speed of an object?
Distance and time
The ability to do work.
Energy
A screwdriver is an example of what simple machine?
A wheel and axle
Solving for time in the speed equation.
What happens when we add a second pulley to a system?
It cuts the force needed in half.
What are the examples of acceleration units?
How do you calculate work?
W= F x D
A seesaw is an example of what class of lever?
First class lever.
How much work is done on a dresser that was pushed 10.5m with 150N of force?
1575 J
A screw with more distance between threads makes work easier or harder?
It makes work harder.