How many hertz vibrations are in a tuning fork for the musical letter f?

During which interval are the persons represented by the graph not moving? a) 0 to 0.5 hrs b) 1.5 to 2 hrs c) 2 to 2.5 hrs d) 4.5 to 5 hrs

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?

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