Cần nâng vật nặng G = 15B lên độ cao 2m bằng mặt phẳng nghiêng dài 12m. Hệ số ma sát giữa vật với mặt phẳng nghiên là f = 0,3. Hãy tính số người có thể tham gia vao công việc, nếu như sức đẩy theo phương song song với mặt phẳng nghiêng của mỗi người là B

What is the earliest point in the universe that we can observe? why can’t we see back further than this?

Organelles are 1. responsible for producing power for the cell 2. tiny structures in the cell that carry out the cell's activities 3. responsible for digestion in the cell 4. found outside of the membrane

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)