Lò co có k= 50 N/m ,vật khối lượng m= 200g dao động điều hòa đoạn thẳng dài l = 12cm ,lấy g=10m/s² , ||²(pi) = 10 Tính biên độ A , tàn số góc w của chuyển động viết phương trình chuyển động của vật vhon gốc thời gian t=0 là lúc vật qua vị trí cân bằng theo chiều dương và chiều âm.

In the sport of parasailing, a person is attached to a rope being pulled by a boat while hanging from a parachute-like sail. a rider is towed at a constant speed by a rope that is at an angle of 15 ∘ from horizontal. the tension in the rope is 1900 n. the force of the sail on the rider is 30∘ from horizontal. what is the weight of the rider? express your answer with the appropriate units.

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

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.