A long, straight wire going through the origin is carrying a current of 3.00 A in the positive z - direction. At a point a distancer = 1.20m from the origin on the positive x- axis. Find the (a) magnitude and (b) direction of the magnetic field. At a point the same distance from the origin on the negative y-axis, find the (c) magnitude and (d) direction of the magnetic field. GIVEN: REQUIRE/S: EQUATION/S: ILLUSTRATION AND SOLUTIONS:

A uniform, 0.0300 kg rod of length 0.400 m rotates in a horizontal plane about a fixed axis through its center and perpendicular to the rod. Two small rings, each with mass 0.0150 kg, are mounted so that they can slide without friction along the rod. They are initially held by catches at positions 0.0500 m on each side of the center of the rod, and the system is rotating at 48.0 rev/min. With no other changes in the system, the catches are released, and the rings slide outward along the rod and fly off at the ends. Part A What is the angular speed of the system at the instant when the rings reach the ends of the rod? Express your answer in revolutions per minute. Wsystem = Submit Part B Wrod = V ΑΣΦ What is the angular speed of the rod after the rings leave it? Express your answer in revolutions per minute. VE ΑΣΦ Submit Request Answer Request Answer ? ? rev/min rev/min

True or false?

The figure below shows the drive train of a bicycle that has wheels 67.3 cm in diameter and pedal cranks 17.5 cm long. The cyclist pedals at a steady cadence of 74.0 rev/min. The chain engages with a front sprocket 15.2 cm in diameter and a rear sprocket 8.00 cm in diameter. Rear sprocket Chain Pedal crank Front sprocket (a) Calculate the speed of a link of the chain relative to the bicycle frame. m/s (b) Calculate the angular speed of the bicycle wheels, rad/s (c) Calculate the speed of the bicycle relative to the road. m/s (d) What plece of data, if any, are not necessary for the calculations? O diameter of front sprocket O diameter of wheels O angular rate O length of pedal cranks O diameter of rear sprocket O none of these