Which of the following best describes work being done by someone's arms?

a. a child building a sand castle

b. a mother holding a baby

c. a boy pushing on a tree

d. a traveler carrying luggage

Which statement describes the relationship between energy and entropy in the universe?

The German V-2 rocket was the first man made object in space

Technician A says that if the opposite DTC can be set, the problem is the component itself. Technician B says that if the opposite DTC cannot be set, the problem is with the wiring or grounds. Which technician is correct?

What are the two opposing forces at work as fusion takes place in stars?

n a location where the train tracks run parallel to a road, a high-speed train traveling at 60 m/s passes a car traveling at 30 m/s in the opposite direction. How long does it take for the train to be 180 m away from the car? Group of answer choices

Which of the following statements is true? A. Both chemical reaction rates and nuclear decay rates vary with the conditions of the reaction. B. Nuclear decay rates vary with the conditions of the reaction, but chemical reaction rates do not. C.

A star may form a black hole once it cannot?

Kai was 200 meters north of the library when he remembered he had to return some books to the library. It took him 200 seconds to do the round trip. Which best describes Kai's roundtrip?

The engine that powers a crane burns fuel at a temperature of 1500 oC. It is cooled by air at a temperature of 20 oC. The crane is used to lift a 1000 kg steel girder 30 m into the air.

The portion of a light ray that falls on a surface is a/an