The velocity of a ball changes from ‹ 8, −4, 0 › m/s to ‹ 7.88, −4.21, 0 › m/s in 0.03 s, due to the gravitational attraction of the Earth and to air resistance. The mass of the ball is 130 grams. What is the equation to find the rate of change of momentum of the ball?

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)

Wind and moving water provide energy. question 1 options: chemical mechanical thermal none of the above

Which of the following compounds would be primarily ionic? methane, ch4, ammonia nh3, calcium chloride, cacl2, or carbon dioxide, co2