Astronomers have proposed the existence of an unexplained force that is causing the expansion of the universe to accelerate. What do they call this force?

dark matter

dark space

dark stars

dark energy

dark holes

A playground merry-go-round has a radius of 3.0 m and a rotational inertia of 600 kg. m2. it is initially spinning at 0.80 rad/s when a 20-kg child crawls from the center to the rim.

An electric ell develops a 450V potential difference between its head and tail. The eel can stun a fish or other prey by using this potential difference to drive a 0.80 A current pulse for 1 ms.

When Aditya pushes on Rachel and her bicycle, they accelerate at 0.22 m/s/s. If Aditya pushes on Rachel and her bicycle with twice as much force, then her acceleration will be? A. 1/4 as much B. 1/2 as much C. twice as much D. the same

Which articulations allow for greatest range of motion?

You are standing on a train station platform as a train goes by close to you. As the train approaches, you hear the whistle sound at a frequency of f1 = 94 Hz. As the train recedes, you hear the whistle sound at a frequency of f2 = 72 Hz.

An unknown solution has a pH of 8. How would you classify this solution? A) The substance is an acid. B) The substance is a base. C) There is not enough information to answer the question.

What is the most abundant element in the universe? A. helium B. hydrogen C. carbon

A bee flies at a constant rate of 5 ms until it notices a flower. It then comes to rest in 5 seconds. Find the acceleration of the bee if a = ΔvΔt

When is there zero net force on an object?

The bending of light when it travels from one material to another is called deflection refraction reflection correction