5. If you hold one end of a Slinky, letting it hang down and then drop it, the top of the Slinky starts to fall but the bottom doesn't drop. Using Newton's First Law of Motion, write a brief
explanation that explains why the bottom of the slinky stays suspended, seemingly
levitating in air for some period of time.

Assuming weightless pulleys and 100% efficiency, what is the minimum input force required to lift a 120 n weight using a single fixed pulley?

The membrane surrounding a living cell consists of an inner and an outer wall that are separated by a small space. assume that the membrane acts like a parallel plate capacitor in which the effective charge density on the inner and outer walls has a magnitude of 7.0 × 10-6 c/m2. (a) what is the magnitude of the electric field within the cell membrane? (b) find the magnitude of the electric force that would be exerted on a potassium ion (k+; charge = +e) placed inside the membrane.

What is the role of lenses in microscopy?