What is the change in internal energy if 20 J of heat is released from a system and the system does 50 J of work on the surroundings?

A.-80 J

B.-20 J

C. 80 J

D. 20 J

What two forces are balanced in what we call gravitational equilibrium?

Explain why a construction worker who uses a jackhammer on a rock does not produce a metamorphic rock.

Which possible discovery would be attributed to an inorganic molecule? a protein that contains more energy than lipids a fireproofing spray used in firefighting a new energy-efficient fuel source a synthetic polymer that resists degrading

Around midcourse, a velocity adjustment is performed to eliminate the small errors introduced when departing from Earth's orbit. This adjustment is performed using one of the onboard thrusters.

The moment of inertia of a body is 3.0 kg x m^2. when its angular velocity is 6.0 rad/s, its rotational kinetic energy in j is

65 million years ago there was a mass extinction that is best known for killing the dinosaurs. There was also a large deposit of dust that contained substances only found in asteroids.

Near which location in New York State would a geologist have the greatest chance of finding dinosaur footprints in the surface bedrock?

E=mc^2 solve for c E/m m/E sqrt (E/m) sqrt (m/E) E - m sqrt (E-m)

For resonance to occur, the object must experience a frequency equal to its what? amplitude period wavelength natural frequency

Rasheed runs a football 10 meters east, turns and runs the football 6 meters west. If his velocity during this run is found to be 3 meters/second, how long does this take Rasheed to complete this run?