Which of the following is true about frictional forces?

telescopes on the earth suffer from the fact that the light coming from the stars has to pass through air or space

Does the biosphere have clear boundaries? explain why or why not.

According to Newton's third law, which describes what happens when a 4.5 kg pumpkin is launched from a catapult with a force of 47.5 Newtons? A. The pumpkin exerts a force of 43 N back against the catapult. B.

What is an intraplate quake? What causes them?

What is the difference between the continental and oceanic crust?

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?