A tightly wound solenoid is 15 cm long, has 350 turns, and carries a current of 3.0 A. If you ignore end effects, you will find that the value of the vector B at the center of the solenoid when there is an iron core of magnetization M = 1.4 × 10^6 A/m is approximately a) 8.8 mT
b) 1.8 mT
c) 7.0 mT
d) 6.2 mT

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?

What’s #16 asking and how do i solve it?

A1-lb collar is attached to a spring and slides without friction along a circular rod in a vertical plane. the spring has an undeformed length of 5 in. and a constant k =25 lb/ft. knowing that the collar is released from being held at a determine, the speed of the collar and the normal force between the collar and the rod as the collar passes through b.