một chất điểm chuyển động trên đường tròn tâm O bán kính R = 50 cm với phương trình góc quét a = 3t^3 - 4t + 5 ( rad ) tính vận tốc góc , vận tốc dài , gia tốc góc , gia tốc tiếp tuyến , gia tốc pháp tuyến và gia tốc toàn phần của chất điểm tại thời điểm t = 1s

Acoil formed by wrapping 80 turns of wire in the shape of a square is positioned in a magnetic field so that the normal to the plane of the coil makes an angle of 28.0° with the direction of the field. when the magnetic field is increased uniformly from 200 µt to 600 µt in 0.400 as, an emf of magnitude 80.0 mv is induced in the coil. what is the total length of the wire?

An equinox occurs when a. neither end of earth's axis is tilted toward or away from the sun. b. the north end of earth's axis is tilted away from the sun. c. the north end of earth's axis is tilted toward the sun. d. earth's axis is parallel to the sun's rays. select the best answer from the choices provided a b c d

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?