When we look at the sun, we are seeing it as it was 8 minutes ago. so we can only see the sun "in the past." when you look at the back of your own hand, do you see it "now" or "in the past"?

An electron and a proton have the same kinetic energy upon entering a region of constant magnetic field and their velocity vectors are perpendicular to the magnetic field. suppose the magnetic field is strong enough to allow the particles to circle in the field. note: you'll need to look up the masses for an electron and proton. 1) what is the ratio of the radii of their circular paths rp/re?

Apair of 10μf capacitors in a high-power laser are charged to 1.7 kv. a. what charge is stored in each capacitor? b. how much energy is stored in each capacitor?

Suppose a comet has an orbital period of 309.1 years around the sun. what is it’s average distance from the sun?