# Physics help books

1. Sep 3, 2005

### clair_a_net

Does anyone have a reconmindation for a physics help book, because i am currently taking phy 121 @ ASU and the TA tend to make things more confusing then making them understandable.

Also does anyone have an easy way to remember fromulas such as acceleration @constant speed, velocity @ constant speed and such, because i'm having trouble remebering them of the top of my head for quizes.

thanks

2. Sep 3, 2005

### LeonhardEuler

Most of us don't know what exactly phy 121 @ASU is. Is it a mechanics course? Is it calculus based? As for those formulas, I think you mean to re-word them. Acceleration at constant speed is zero if the particle is not changing direction, and if it is then this is kind of a very riddle-ish way of asking for the formula $a=\frac{v^2}{r}$ where r is the instantaneous radius of curvature. Likewise, velocity at constant speed is just the initial velocity if the particle is not changing direction, and if it is changing direction, then the velocity is just whatever it happens to be; there's no way of telling. In general a good way of remembering formulas is remembering how they are derived.