SCALCET8 6.4.007.MI. A force of 8 lb is required to hold a spring stretched 4 in. beyond its natural length. How much work W is done in stretching it from its natural length to 10 in. beyond its natural length?

The two required components for a generator

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.

Ahuge (essentially infinite) horizontal nonconducting sheet 10.0 cm thick has charge uniformly spread over both faces. the upper face carries +95.0 nc/m2 while the lower face carries -25.0 nc/ m2. what is the magnitude of the electric field at a point within the sheet 2.00 cm below the upper face? (ε0 = 8.85 × 10-12 c2/n · m2)