Abox is at rest on a table. what can you say about the forces acting on the box?
the upward( blank) and the downward (blank) are balanced.

applied force drag force
frictional force gravitational force
normal force tension

The frequency of a given region of the electromagnetic spectrum ranges from 3 × 1016 − 3 × 1019 hertz. which type of wave is found in this region? a. x-rays b. ultraviolet rays c. infrared waves d. radio waves

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.