What force could prevent the universe from expanding forever

do bowling balls float? (I know the answer i just want to see how many other people know. also answer as in depth as you can)

Would the springs inside a bathroom scale be more compressed or less compressed if you weighed yourself in an elevator that accelerated upward? Accelerated downward?

Why there are not green stars?

An air pump does 5,600 J or work to launch a water bottle rocket into the air. if the air pump applies 150 N of force to the rocket at an angle of 45 degrees to the ground, what is the horizontal distance the water bottle rocket travels?

Most comets have short periods and orbit close to the ecliptic plane. (T/F)

Which planet, when viewed through a telescope, appears as a reddish ball interrupted by some permanent dark regions that change intensity?

A wave has a wavelength of 10 mm and a frequency of 5 hertz. What is its speed? a. 50 mm/s b. 50 hertz's c. 2 mms d. 0 0.50 mms

Suppose you illuminate two thin slits by monochromatic coherent light in air and find that they produce their first interference minima at / pm 35.09 degrees on either side of the central bright spot.

Tala wants to create a sound echo. She can create the echo using a pane of glass or a carpet square. Which one does she choose? Explain.

a the average distance from the Sun to Pluto is approximately 6.10 x 1 0 ^9. how long does it take light from the sun to reach Pluto?