4. A worker exerts 140 N to push a 15 kg crate 20 meters across the floor. He then lifts the crate 2 meters up to a shelf.
a. How much work is done to push the crate across the floor?
b. What work was done to lift the crate up?
c. What was the total work done by the worker?

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

Frequency of electromagnetic waves that a radio station is assigned. what do you call this type of wave?

Which statement best describes what energy transfer diagrams show? energy can change form, but the total amount of energy stays the same. every energy transformation results in a reduction of energy energy transformations result in fewer types of energy each type of energy can change into one other type of energy