Aphysics student rests her backpack upon his shoulder. the backpack is suspended motionless by one strap from one shoulder. which free-body diagram best represents this situation?

Along wire carrying a 4.2 a current perpendicular to the xy-plane intersects the x-axis at x=−1.7cm. a second, parallel wire carrying a 3.0 a current intersects the x-axis at x=+1.7cm. part a at what point on the x-axis is the magnetic field zero if the two currents are in the same direction? express your answer to two significant figures and include the appropriate units.

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton

Asemipermeable membrane is placed between the following solutions. which solution will decrease in volume? solution a: 1.4% (m/v) starch solution b: 7.62% (m/v) starch