Amass of 240 g oscillates on a horizontal frictionless surface at a frequency of 3.0 hz and with amplitude of 4.5 cm. (a) what is the effective spring constant for this motion? (b) how much energy is involved in this motion?

The place you get your hair cut has two nearly parallel mirrors 6.00 m apart. as you sit in the chair, your head is 2.00 m from the nearer mirror. looking toward this mirror, you first see your face and then, farther away, the back of your head. (the mirrors need to be slightly nonparallel for you to be able to see the back of your head, but you can treat them as parallel in this problem.) how far away does the back of your head appear to be?

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

Two polarizers are oriented at 40∘ to each other and plane-polarized light is incident on them. if only 16 percent of the light gets through both of them, what was the initial polarization direction of the incident light?