Một vật nhỏ nặng m=200g, gắn vào lò xo nằm ngang có độ cứng K. Vật dao động điều hòa với phương trình x=6cos(ωt+ pi/2) (cm/s). Biết trong thời gian t = 1/30 giây đầu tiên vật đi được S = 9cm. Tính K và năng lượng dao động của vật

multiple

think its the third option

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initial speed when it is dropped is 150 ft/s

now at the same moment the acceleration due to gravity is perpendicular to its velocity

so as we know that

now we have centripetal acceleration a = 32 ft/s^2 as its perpendicular to velocity

while tangential acceleration at the same moment will be zero

so

now radius of curvature is given as

so the radius of curvature just after it is dropped is 703.125 ft