As you have learned, an electromagnet is a magnet that is produced by electric current. Think about how electromagnets are used and what you have seen or heard of them being used for. In your initial discussion post, respond to the following: Which of the principles or laws discussed in this module explain how an electromagnet works? Describe in detail two modern applications of electromagnets.
Do these electromagnets draw a large amount of current or a little?
How do you know?
What supplies that current?
Why do you think electromagnets are used in these different ways?
What is the advantage of using an electromagnet rather than a permanent magnet?

An experiment is designed to test the relationship between the initial height of a basketball before it is dropped to the height of its rebound bounce. the height of the rebound bounce is measured using a scale positioned behind the ball. in the above experiment, which condition would not be controlled? a). the starting height of the ballb). the surface the ball bounces on c). the type of ball d). the method to measure the rebound height of the ball

Aparticle of mass m is projected with an initial velocity v0 in a direction making an angle α with the horizontal level ground as shown in the figure. the motion of the particle occurs under a uniform gravitational field g pointing downward. (a) write down the lagrangian of the system by using the cartesian coordinates (x, y). (b) is there any cyclic coordinate(s). if so, interpret it (them) physically. (c) find the euler-lagrange equations. find at least one constant of motion. (d) solve the differential equation in part (c) and obtain x and y coordinates of the projectile as a function of time. (e) construct the hamiltonian of the system, h, and write down the hamilton’s equations (canonical equations) of motion.

Which law represents the thermodynamic statement of the conservation of energy of a system? a. the fourth law b. the first law c. the second law d. the third law