Calculate the centripetal acceleration and the centripetal force acting on a wooden block. Recall that the block's mass is 0.21 kg, with radius 0.70 m, and the block makes 15 rotations in 18.4 s.
2007-10-01 04:46:51 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
a = v^2/R is the centripetal acceleration along the R of the block, where R is the radius of rotation and v is the tangential velocity = wR, w = angular velocity = radians/sec = N2pi/T and N = 15 rotations and T = 18.4 sec. The 2pi constant changes the rotations to radians, something we need to do when working with R.
Thus a = v^2/R = (wR)^2/R = w^2 R = (N2pi/T)^2 R; you can do the math.
Like all force equations, f = ma; in this case the a is the centripetal acceleration you just found. m = .21 kg. Again, you can do the math.
Couple of things to keep in mind. We need to convert rotations to radians for unit consistency with R. (radians are actually defined by R and circumference of a circle.) Second, the force from an acceleration is still f = ma no matter which way the a is pointing. So, as this a is along the direction of R, it is centripetal acceleration and the force from it is centripetal force.
2007-10-01 06:25:10 · answer #1 · answered by oldprof 7 · 0⤊ 0⤋
The cyclist is decreasing speed at a rate of 0.5ms^-2 This means that at any time, or velocity his tangential acceleration is 0.5. So when he is travelling at 10ms^-1, his tangential acceleration is 0.5ms^-2 Technically because he is slowing it is -0.5ms^-2. The centripetal acceleration is given by: a = v^2 / r at v = 10, r = 30 a = 100 / 30 a = 10/3 ms^-2
2016-05-18 00:44:12 · answer #2 · answered by ? 3 · 0⤊ 0⤋