Two springs with the same unstretched length, but different force constants k1 and k2 are attached to a block with mass m on a level, frictionless surface. Calculate the effective force constant keff in each of the three cases depicted in the figure (Figure 1). (The effective force constant is defined by ∑Fx=−keffx.) Figure1

What occurs during a combustion reaction

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.

The field between two charged parallel plates is kept constant. if the two plates are brought closer together, the potential difference between the two plates either a) decrease b) does not change c) increase?