Hello i would like to know if there is a course or a book in which to learn quantum mechanics is easier, i am currently studying quantum mechanics, but it is a little complicated because i have some mathematical doubts, but nevertheless i would like to know if there is a course or book that explains and develops the problems so that they are understandable. and if there is no book or course i would appreciate an honest and complete answer, you very much and greetings.
sorry i know that this is not a problem but what better to ask the experts do not believe.

As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is 100) a) static friction. b) kinetic friction. c) a combination of static and kinetic friction. d) neither static nor kinetic friction, but some other type of friction. e) it is impossible to tell what type of friction acts in this situation.

Astudent is performing an experiment comparing sound and light waves. the student gathers the following data. what conclusion does the student most likely make based on this data? light waves always travel the same speed; however, the speed of sound is determined by the medium that it travels through. all sound waves always have the same energy, so the temperature of the medium does not affect wave speed. light needs to vibrate particles, so it travels fastest in tightly packed solids, while sound does not need a medium, so it travels fastest in a gas. tightly packed particles in solids slow down the light waves; however, sound waves make particles bounce into each other, so they travel faster in solids.

10 newton object is placed 3 meters from the fulcrum. at what distance on the other side would you need to place a 15 newton object to balance the lever? show your work!