How does sandpaper increase friction

If you are doing a "rowing" motion, what muscle of the shoulder are you using?

What four things happen during a solar eclipse?

A bike rider pedals with constant acceleration to reach a velocity of 7.5 (vf) m/s over a time of 4.5 s (t). during the period of acceleration, the bike's displacement is 19 m (d). what was the initial velocity of the bike?

A circut contains a 2 microfarads and a 20 microfarads capacitor connected in parallel. What is the total capacitance of the circut? A. 9.6 mf B. 1.8mf C. 22mf D. 18mf

3. For the following questions, use a periodic table and your atomic calculations to find the unknown information about each isotope: You have a Nitrogen Isotope with a mass number of 15. How many neutrons are there? 15 7 8 14

A solid sphere of radius R has a total charge Q distributed evenly throughout its volume. What fraction of the total charge is located inside a radius R/2?

What is Nothing. (sorry i have been wondering this for a very long time)

What is the speed of a bobsled whose distance-time graph indicates that it traveled 123m in 28s?

Eric has a mass of 80 kgkg. He is standing on a scale in an elevator that is accelerating downward at 1.7 m/s2m/s2. What is the approximate reading on the scale?

Without the force of friction, people would not be able to walk.