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Physico- obj 1 CCBBCBDBCD 11 DACADCAADB 21 BACBBBDDBD 31 DDDBDABABA 41 BCAADABCDC 8a) Net force: The net force is the vector sum of all the forces that act upon an object. It is also the sum of all the forces, taking into account the fact that a force is a vector and two forces of equal magnitude and opposite direction will cancel each other out. 8b) The law of conservation of linear momentum states that the total momentum of a system of particles remains constant, so long as no external forces act on the system. e.g Firing a bullet from a gun or a radioactive nucleus spontaneously emitting an alpha particle. 8c) M = 200g = 0.2kg, h= 2cm, h2= 1.8m, u = 0, v=? P.E = mgh P.E = K.E = 1/2MV^2 4 = 1/2 x 0.2 x V^2 V = √40 = 6.32m/s^-1 Impulse = M(V-U) Impulse = 0.2 ( 6.32 - (-o)) = 1.264Kgms^-1 8d) M= 0.02kg , f= 5Hz, x= 10cm = 0.1 , V = 200cm = 2m/s 8dii) r = ? , w = 2πf = 2x3.142x5 W= 31.4 From V= w √r^2 - 0.1^2 2 = 31.4 √ r^2 - 0.1^2 = r^2 - 0.1^2 = 0.6369^2 r^2 = 0.41564161 r = √ 0.41564161 r = 0.64m Maximum vel V = wr (x = 0 at maximum) 8diii) maximum potential energy =1/2 MVm^2 =1/2*20^10 *(372.3)^2 =10*138596.4 =1385964J ========== 10a) Critical angle is the angle of incidence in the optically densed medium when the angle of refraction is 90degrees 10b) Anti-note are created by region of maximum displacement in a wave more coming ================================ 11a) Dielectric strength is the property of an insulating material to retain material to retain electrical properties 11bi) -Infra-red wave -Geiger muller counter -Scintillation counter 11bii) Irradiation of solar energy 11c) Charge(q)=1.0*10^-19C Electric field intensity(E)=1200NC^-1 Weight of the oil drop=? E=F/q 1200=F/1.0*10^-19 F=1200*1.0*10^-19 F=1.2*10^3*10^-19 F=1.2*10^-16N 11d) R=100ohm, L=0.05H, C=0.25uF V=220v, f=50Hz 11di) Impedance(z)=sqroot(R^2+(Xl-Xc)^2) Xl=2*pie*fl Xl=2*(22/7)*50*0.05 Xl=15.71ohm Xl=(1/2*pie*fc) Xc=1/78.55*10^-6 Xc=10^6/78.55 =12730.7ohm Z=sqroot(100^2+(15.71^2-12730.7^2) Z=sqroot(10000+2.63*10^16 Z=sqroot(2.63*10^16) Z=1.62*10^16ohm 11dii) Vrms=IZ I=220/1.62*10^16 =1.36*10^-14 ================================ 9a) i) thermal equilibrium is the point at which the temperature of an object remain constant or steady ii)fundamental interval is the distance between upper and lower fixed point of a thermometre 9b) i) it can be used to raise heavy load ii) it is used in printing press 9c) magnet 9di) by using calometry law heat last = heat gain MmCmDθm=CaDθ + Mw Cw Dθ 300 Cm ( 85 - 40 ) = 90 + 500 * 4200 13500Cm = 90 + 29400000 13500CM = 29400090/13500 Cm=2177.78Jg^-K^-1 9dii) § i) by convection ii) by conduction 9diii) § i) power generation ii) chemical processing ======================== 5) i) For launching astronauts into the space ii) For launching satellite iii) For Scientific research ================================ 6a) Doping is the addition of small quantity of an element to a semi conductor to change its characteristics 6b) Doping introduce impurities into an extremely pure instrintic semi conductor for the purpose of modulating its elctrical properties ================================ 7) X = Electron gun Y = Accelerating mode Z = Deflection plate ================================ 3) -smoke -aerosol -dust particle ================================ 1a) impulse(I)=F*t F=ma= m(v/t)= M((d/t)/(t)) f=M(l/T)/T)= MLT^-2 I=MLT^-2 * T I=MLT^-1 1b) Acceleration(a)=v/t=(d/t)/t a=d/t^2= L/T^2= LT^-2 1c) WOrk(w)=f*d W=MLT^-2 * L W=ML^2T^-2 °=========°================° 4) Given flux density(B)=0.217 Force(F)=9.6*10^-12N Speed(v)=? F=Bqv 9.6*10^-12= 0.12* 1.6* V V=(9.6*10^-12)/0.192*10^-19 =50*10^-12+9 v=50*10^7 =5*10^8ms^-1 ================================ 2) Velocity(u)=20ms^-1 Angle(tita)=40 degree At maximum height, h V^2=u^2 + 2gh U^2 sin^2 tita+u u= 20^2* (sin 40 degree)^2 u=20^2*(sin 4o degree) u=400* 0.3455 u=138.2ms^-1