Physics 2 MIDTERM REVEIW
Physics 2 MIDTERM REVEIW PHYS 1155
Popular in Physics for Engineering 2
verified elite notetaker
Popular in Physics
This 17 page Study Guide was uploaded by Aubrey Kenderdine on Sunday October 16, 2016. The Study Guide belongs to PHYS 1155 at Northeastern University taught by Latika Menon in Fall 2016. Since its upload, it has received 5 views. For similar materials see Physics for Engineering 2 in Physics at Northeastern University.
Reviews for Physics 2 MIDTERM REVEIW
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/16/16
Physics 2 for Engineering Midterm Review Electric charge- measured in coulombs (C) An electron has a charge of 1.6 x 10 -19C Electric force = force between charged particles Magnitude of force on q (a1charged particle) by q (an2ther charged particle) = the magnitude of force on q b2 q 1 Direction depends on signs of charges (same charge repelling and opposite charges attracting) Coulomb’s Law 2 Fe12 = kq1 2/r Fe12 is electric force on 1 due to q2 k is constant equal to 8.99 x 10 Nm /C2 2 q is charge of each particle r is distance between charges in meters Electric field- force per unit charge E = F/q Direction depends on charge From a positive charge, the electric field points out From a negative charge, the electric field points in Force depends on the interaction between two charges (repulsion or attraction) If q is positive, F has the same direction as E If q is negative, F has the different direction as E Dipole Two identical charges of opposite signs Charge goes from negative to positive Dipole moment (p) separated by distance (d) p = q d Dipole moment in Cm (coulomb meters) Electric field due to ring of charge has 3-D electric field (cone shaped) Torque- force to rotate object Torque is maximum when dipole is perpendicular to electric field Torque is minimum when dipole is parallel or antiparallel to electric field Simple harmonic motion- oscillating about an equilibrium position At equilibrium position, the sum of all forces is 0 Oscillation- sin/cos wave for position vs. time Velocity is 0 at peaks and troughs Amplitude is height of a peak or depth of a trough A period is one whole cycle of a peak and a trough T = 1/f Period is the inverse of frequency At velocity = 0, kinetic energy = 0 and potential energy is at maximum Metal sphere = conductor Surface charge σ = Q / A Insulator Charge distributed over the volume ρ = Q / V Gauss’s Law Charges inside closed surfaces (Q = enclosed charge) 2 ϕ is electric flux (electric field and area product in N*m /C) ϕ = E * A = Q / Ɛ 0 Gaussian surface must be symmetric For point or sphere charges, Gaussian surface has a spherical distribution For linear or sheet charges, Gaussian surface has a cylindrical distribution For a conducting sphere on the circumference, E = q / (4 π Ɛ R ) 0 2 Eon the inside of a conducting sphere = 0 λ = Q / L (charge per unit length) For a long wire E = λ / (2 π r Ɛ )0 For a cylinder E = q / (2 π r L Ɛ )0 For an infinitely thin sheet E = σ / 2 Ɛ 0 For an infinitely large object with thickness E = σ / Ɛ 0 Electric potential energy is a scalar quantity in Joules (J) U = kQq / r Electric potential is a scalar quantity in volts (V) 1 V = 1 J / C Unit of electric field E is N / C or V / m V = kq / r ΔV = - E * d at constant electric field For collection of point charges V = Σ kQ / r V = U / q U = qV E direction points from positive charge to negative charge Positive charge moves in the direction of E from high to low potential Negative charge moves opposite to the direction of E from low to high potential E is perpendicular to equipotential lines Point charge- equipotential lines are spherical Infinite line- equipotential lines are cylindrical Infinite sheet- equipotential lines are flat surfaces For infinitely long cylinder or wire, V –bV = -aλ / 2πƐ * ln0(r /r )b a For ring of charge, V = Q / 4 π Ɛ √(0 + a ) 2 Capacitors store charge C = Q/V Unit is Farads, 1 Farad = 1 C/V Parallel Plate Capacitor C = A Ɛ / 0 Capacitors in series Charge on each capacitor is the same Voltage on each capacitor is different Applied volt is the sum of volt on the two capacitors (V = V +V ) 1 2 1/C eq1/C +11C 2 Capacitors in parallel Voltage (potential) on each capacitor is the same Charge on each capacitor is different (Q = Q +Q ) 1 2 C eq +C1 2 Energy stored in capacitor, U= (1/2) Q / C= (1/2) C V = (1/2) Q V Energy density, u = U/V= (1/2) Ɛ E 0 2 Dielectric when charge Q is constant Dielectric constant (of specific material), K=V /V=C/C 0 0 E = (σ- σ)i/ Ɛ 0where σ is the induced charge) Spherical capacitor C = 4π Ɛ (0 ra b(r -ar )b
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'