m013 When the temperature of a metal is decreased its electrical resistance decreases because conduction electrons loss less energy in collisions with the lattice ions whose vibrations decrease by lowing the temperature. m020 Power transmission see notes – Magnetic levitation trains see notes – – m045 = 102.8 MHz = 102.8106 Hz f = ? J = ? eV = ? m E = 1.60210-19 C = 3.0 m.s-1 = 6.62610-34 J.s qe c h = E(J)/qe E = h f E(eV) c = f = c / f 6.810-26 J = 4.310-7 eV E = very small photon energy since in radio part of em spectrum = 2.9 m long wavelength because of small frequencies m047 (a) Cathode rays were deflected by electric and magnetic fields negatively charged particles. J.J. Thompson was able to measure ratio electrons qe/me (b) To produce an electrical discharge need very high voltages > 10 000 V – (c) make sure that your do not come into contact with the high voltage source m049 proton = 1.610-19 C = 6.00 m.s-1 = 1.82 T = 0.350 m q v B R = ? kg = ? kg m m0 Magnetic force = Centripetal force m050 Paddle spins when struck by cathode ray beam beam carries momentum m065 CRO step-up transformer Transistor circuit step-down transformer
m013 When the temperature of a metal is decreased its electrical resistance decreases because conduction electrons loss less energy in collisions with the lattice ions whose vibrations decrease by lowing the temperature. m020 Power transmission – see notes Magnetic levitation – trains – see notes m045 f = 102.8 MHz = 102.8106 Hz E = ? J = ? eV = ? m qe = 1.60210-19 C c = 3.0 m.s-1 h = 6.62610-34 J.s E = h f E(eV) = E(J)/qe c = f = c / f E = 6.810-26 J = 4.310-7 eV very small photon energy since in radio part of em spectrum = 2.9 m long wavelength because of small frequencies m047 (a) Cathode rays were deflected by electric and magnetic fields negatively charged particles. J.J. Thompson was able to measure qe/me ratio electrons (b) To produce an electrical discharge – need very high voltages > 10 000 V (c) make sure that your do not come into contact with the high voltage source m049 proton q = 1.610-19 C v = 6.00 m.s-1 B = 1.82 T R = 0.350 m m = ? kg m0 = ? kg Magnetic force = Centripetal force m050 Paddle spins when struck by cathode ray beam beam carries momentum m065 CRO step-up transformer Transistor circuit step-down transformer
p7_ans.docx