Question

A student obtained the following graph of velocity versus time. If the mass of the cart plus the tack is 15.0 g, the added mass is 500 g, and the radius of the circular motion was 17.0 cm, (a) what was maximum force exerted by the magnets? (b) What is the tangential acceleration of the cart just before the breakaway occurred. I am stuck on part b.

160 40 0 02 0 a 0.4 0.8 t (S)

Answer 1

Given that A student obtained the following graph of velocity versus time as shown nbelow graph. Graph: - velocity versus time \r\n Total mass m = 500 + 15 = 515 g = 0.515 kg circular radius R = 17 cm = 0.17 m slope of line AB = 100 - 0/0.5 - 0 = 100/0.5 = 200 v in/sec slope of line BC = 140 - 100/0.8 - 0.5 = 40/0.3 Slope of line AB > slope of line Bc > velocity in A rightarrow B rightarrow velocity in B rightarrow C maximum central petal force = mv^2/R = 0.515 (200)^2/0.17 = 121.1764 kv \r\n (a) maximum force exerted by the magnets. Therefore the maximum force exerted by the magnets is = 121.1764 ku (b) the tangential acceleration of the cart just before the breakaway occurred. Tangential acceleration = R alpha = R[dw/dt] At just before breakaway occurred the velocity �v� and thus angular velocity is constant. Because AB n a line