In a simple electric circuit, ohm's law states that v=irv=ir, where vv is the voltage in volts, ii is the current in amperes, and rr is the resistance in ohms. assume that, as the battery wears out, the voltage decreases at 0.030.03 volts per second and, as the resistor heats up, the resistance is increasing at 0.040.04 ohms per second. when the resistance is 200200 ohms and the current is 0.040.04 amperes, at what rate is the current changing?

An athlete swings a ball, connected to the end of a chain, in a horizontal circle. the athlete is able to rotate the ball at the rate of 8.13 rev/s when the length of the chain is 0.600 m. when he increases the length to 0.900 m, he is able to rotate the ball only 6.04 rev/s. (a) which rate of rotation gives the greater speed for the ball? 6.04 rev/s 8.13 rev/s (b) what is the centripetal acceleration of the ball at 8.13 rev/s? m/s2 (c) what is the centripetal acceleration at 6.04 rev/s? m/s2