Mathematica needs you! Add, subtract, divide and multiply your way to victory. Meet the Karate Cats and practice spelling, grammar and punctuation as you chop, kick and smash the challenges. Join ...

Note that all forces on the system act at the fixed point O. What does this say about the angular momentum of the system about point O? Also, consider the work/energy equation for the system.

It is desirable that the common reference points are presented in different ways for different purposes. For some purposes it will however be appropriate to summarise the set of proposed Common ...

Trump’s Complaint About Israeli Strike on Gas Field Exposes Divergent Strategies President Trump said he told Prime Minister Benjamin Netanyahu he disapproved of the attack. But Israeli officials said ...

President Trump has encouraged states to pursue the death penalty. The New York Times editorial board argues it is a cruel and unjust punishment. What do you think? By Natalie Proulx A guest essay ...