PHYSICS CHALLENGE

Newtonian Dynamics

A block of mass 4kg is pushed against a horizontal spring with a spring constant of 500 N/m, compressing it by 0.2m. The block is then released and slides across a frictionless surface until it hits a vertical wall. Calculate the speed of the block just before impact using the principle of conservation of energy.

Chemistry Question of the Day

Consider the following reaction: 2A + 3B → C + D. If the rate of disappearance of A is 0.04 mol/L·s, what is the rate of formation of C? (Hint: Use the stoichiometric coefficients to relate the rates of reaction.)