Raindrops fall 1.61×103 m from a cloud to the ground. If they were not slowed by air resistance, how fast would the drops be moving when they struck the ground?

In a hydrogen molecule there are a total of four charges, 2 protons in the two nuclei, and 2 electrons. how many unique charge-pairs are there (without double counting)?

In an old-fashioned amusement park ride, passengers stand inside a 3.0-m-tall, 5.0-m-diameter hollow steel cylinder with their backs against the wall. the cylinder begins to rotate about a vertical axis. then the floor on which the passengers are standing suddenly drops away! if all goes well, the passengers will “stick” to the wall and not slide. clothing has a static coefficient of friction against steel in the range 0.60 to 1.0 and a kinetic coefficient in the range 0.40 to 0.70. part a what is the minimum rotational frequency, in rpm, for which the ride is safe? express your answer using two significant figures. f f = rpm

Bahan yang digunakan mencegah terjadinya polarisasi pada batu baterai a.larutan h2so4b.mncl2 dan serbuk karbonc.pbso4d.nh4cl