What is the evidence that a large fraction of the matter in the universe is invisible?

A guitar string with mass density μ = 2.1 * 10-4 kg/m is L = 0.95 m long on the guitar. The string is tuned by adjusting the tension to T = 82.6 N. With what speed do waves on the string travel?

A force of 200 N is applied at piston A, which has a surface area of 4 cm 2. The pressure is transferred through oil to piston B which applies a force of 3000 N. Calculate the surface area of piston B.

When do both hemispheres receive the same amount of the sun's energy? Question 9 options: both autumnal equinox and vernal equinox only winter solstice only vernal equinox only autumnal equinox

Two circular coils are concentric and lie in the same plane. The inner coil contains 140 turns of wire, has a radius of 0.015 m, and carries a current of 7.2 A. The outer coil contains 180 turns and has a radius of 0.023 m.

What is the mass of an object that has a density of 3.2 g/cm^3 and a volume of 5.5cm^3? (The density of an object has the equation d = m/v.)

In most cases, a multicellular organism is not an exact copy of its parents because it

In the study that the FBI did on examining the physical characteristics of hair, what percentage of the "matches" were not really matches at all?

Evaporation only occurs at the surface of a liquid

Which of these substances has the highest pOH? 0.10 M HCl, pH = 1 0.001 M HNO3, pH = 3 0.01 M NaOH, pH = 12

A climber pulls herself 8 meters upwards with a force of 150 Newtons. If it takes her 16 seconds to cover the 8 meters, how much power is she using? A. 40 W B. 55 W C. 70 W D. 75 W