Two long, parallel conductors separated by 10.0 cm carry currents in the same direction. The fi rst wire carries a current I1 _ 5.00 A, and the second carries I2 _ 8.00 A. (a) What is the magnitude of the magnetic fi eld created by I1 at the location of I2? (b) What is the force per unit length exerted by I1 on I2? (c) What is the magnitude of the magnetic fi eld created by I2 at the location of I1? (d) What is the force per length exerted by I2 on I1?

Gravity on Simple Harmonic Motion (14.5) *ωt = phase (radians) → Vertical Oscillations in SHM are not affected by gravity Fx net ma x -kx −k a x m x → acceleration no longer always constant a = d2x = −kx → a = x’’(t) x dt2 m x x(t) = Acos(ωt + ϕ) x’’(t) =− Aω cos(ωt + ϕ) = a x −kx = mkAcos(ωt + ϕ) → −k= ω 2 m m Period T = 1/f = 2π /ω f = ω 2π / T = 2π m k (mass and k affect T and f, A has no effect) √ / Energy in Simple Harmonic Motion 14.3 Computing Total Energy: 1 - Moving = KE = mv 2 2