Question

A spark is generated in an automobile spark plug when there is an electric potential of 3000 V across the electrode gap. If 50 W of power is generated in a single spark that lasts 100 ns, what is the total charge delivered across gap? 0.80 nC 1.67 nC 3.53 nc 6.52 nc 10.0 nC

Answer 1

Solution Electric potential = v= 3000 v Power generated =P = 50W Time = t = loons=100 xlos Formula of Power Power = P = VI p=VI - (Uring t o is charge P = vxQ Using I = Q vxQ f -9 8 = P xt = Soxlooxlo V 3000 Q = 1.67X10 C = 1.67n6 Q Hence total change delivered acros gab is 1.67 nc

So Enaguatic = 2 up=mo? with same radius d. A proton and an alphe particle are traveling speed enter a uniform maguitricfell If a charge & having velocity & enter in a magnetic field such that velocity vector is pepenkiolas to magnetic field B then the force afflied by magnetic field on the charge is Emagnetic This Force will provide centripetal force and charge starts to 'sevolve in circular orbit having of charge mu? Centripetal - 2 VB am - mass Force r Mass of Proton mp=1.67x16 16-27 kg Charge of Proton -te (e= 66 810-19 () Therefore 2 p & B = mg rProton mp > 0 - qB Proton

-27 mass - malpha ob - maple ut of alpha particle = 6.64x10 kg charge of alpha particle = Zalpha therefore 2 Raifta -tze Halpha v alpha 2 B - malpha ralpha 0 Divide Equation 2 by mething that 2 B alpha 2 B Manton / renton Proton Ealpha Proton malpha X Proton Merton X r alpha -27 +24 x 7.67X10 x mProton Palpha r Proton ralpha +8X 6,64X10-27 Enston X m alpha Proton Ralpha 2 X 1067 -0.5 6.64 Hence proton halpha = 0.5

an average power of 2mW 1x10 3m A Laser pointer delivers in a circular beam of 2 mm diameter. Power = P = 2mW = 2x10 3 W Diameter = 2mm radius, r= 1 mom = Area of circular beam = A=11&² A = 3.14x(10-3² m A = 3.14x100 m² Formula of Average Energy Density Power E- Area x speed of light P=22103W pe - 2x 10 8 C-3x10 my sec E = AXC -5 3.148106x3X108 E = 0.21 x 16 E = 2.18106 / cubic meter E = 2.1 E6 / cubic meter Hence, Average Energy density in the beam is 2.1E-6 cubic meter