All the forces within a closed system are

a) internal

b) external

c) due to gravity

d) angular

Which statement best describes a relationship amongst hypotheses, theories, and laws? A hypothesis is used to explain laws and theories. A law is used to explain a hypothesis and theories. A hypothesis combines several theories.

A balsa wood raft is 1.50 m long, 1.00 m wide, and 0.120 m high. the density of balsa is 380 kg/m^3. what is the mass of the raft? (unit=kg)

Explain what happens to a boat on a river when a man jumps out of it into a nearby shore

A spaceship moving through deep space will continue moving at the same speed forever. What is the name of the property that allows this to happen? A. Force B. Normal force C. Mass D. Inertia

Your friend of mass 50 kg can just barely float in fresh water. Calculate her approximate volume.

Why is thermal energy from the Sun transferred to Earth through electromagnetic waves instead of any other type of thermal energy transfer? Electromagnetic waves can carry energy through matter. Electromagnetic waves can travel through empty space.

Why do different elements emit different colors of light

In an experiment, 108 J of work was done on a closed system. During this phase of the experiment, 79 J of heat energy was added to the system. What was the total change in the internal energy of the system?

J. J. Thomsons experiments provided evidence that an atom

How does our sun differ from most other main sequence stars?