An infinitely long cylindrical shell of uniform volume density has an inner radius a and an outer radius b. what infinite line of charge must be places at the center of the cylinder (r=0) to make the external (r> b) electric field zero?

divide the right side by the left side

0.024÷1.2=0.02 for example

the force required to move the cart is divided by three or 33.33 n.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27