What does it mean when someone says that knowledge cannot be assessed or measured without demonstration? How does this relate to academics?

Why do we believe that most of the mass of the milky way is in the form of dark matter?

The density (mass divided by volume) of water is 1.00 g/cm3. What is this value in kilograms per cubic meter?

A cube has a drag coefficient of 0.8. what would be the terminal velocity of a sugar cube 1 cm on a side in air (ρ = 1.2 kg/m3) ? take the density of sugar to be 1.6 x 103 kg/m3.

If you went to a planet with an acceleration due to gravity of 20 m/s^2 and twirled a bucket of water, what happens to the angular speed you need to twirl the bucket to keep the water in?

Tells the speed or direction of an object

An alpha particle travels at a velocity of magnitude 550 m/s through a uniform magnetic field of magnitude 0.045T. (An alpha particle has a charge of charge of + 3.2 x 10-19 C and a mass 6.

A woman tries to put lipstick in the car. She has to come to a fast stop, and the lipstick falls to the floor and rolls forward, under the brake pedal. She dies. Why does this happen?

The slope of the line on any speed vs time graph is equal to the objects?

True or False? a globular cluster is a group of older stars that are clustered together.

The doppler effect is the change in observed frequency due to