What is the nature of image of Sun obtained on a paper with the help of concave mirror

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?

What about a rubber band, can it change its shape? is it a solid?

Consider lifting a box of mass m to a height h using two different methods: lifting the box directly or lifting the box using a pulley (as in the previous part). what is wd/wp, the ratio of the work done lifting the box directly to the work done lifting the box with a pulley?