Derive an expression for the magnetic field strength at distance d from the center of a straight wire of finite length l that carries current i. express your answer in terms of the variables d, l, i, and appropriate constants. part b)determine the field strength at the center of a current-carrying square loop having sides of length 2r. express your answer in terms of the variables r, i, and appropriate constants. part c)compare your answer to part b to the field at the center of a circular loop of diameter 2r. do so by computing the ratio bsquarebcircle. express your answer to two significant figures and include the appropriate units.

Lin yao looks at the back of a spoon. how should she describe her reflection? upside down and smaller upside down and larger right-side up and smaller right-side up and larger

Thomas his older brothers, who own a junk yard, on the weekends to earn extra money. he likes to them push broken-down cars to the back of the junk yard because it makes him feel strong. last saturday, they pushed three cars with different weights, and he noticed he used different amounts of force for each one. the cars were the following weights: white car: 2,700 kg red car: 1,500 kg blue car: 2,100 kg think about how much force is needed to move each car. which correctly lists the cars in order from the most to least amount of force needed to move them? a) white, blue, red b) blue, red, white c) red, white, blue d) white, red, blue

A0.580-kg rock is tied to the end of a string and is swung in a circle with a radius of 0.500 meters. the velocity of the rock is 4.50 m/s. what is the centripetal force acting on the rock? 15.5 n 5.22 n 69.8 n 23.5 n