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[quote uid=merrylarry pid=1122] Theory Part 1a i.Insulated wire iimagnet iiicopper coil. 1B. i. A rocket can work anywhere even in space. ii. A rocket is fast and thus saves time. iii. Rockets are used for space shuttles. 1C i They are applicable in the heating of swimming pool water. ii. They can be applied as solar panels. 3a. A trajectory is the curved path of an object that has been fired or thrown/ a path followed by a projectile. 3B. i.The force ii. The mass of the body. iii. The surface area of the projectile No9 In silver plating a spoon,it is made from the cathode of an electrolytic cell. The anode is a bar of silver metal, and the electrolyte (the liquid in between the electrodes) is a solution of silver cyanide, AgCN, in water. When a direct current is passed through the cell, positive silver ions (Ag +) from the silver cyanide migrate to the negative anode (the spoon), where they are neutralized by electrons and stick to the spoon as silver metal: Meanwhile, the silver anode bar gives up electrons to become silver ions: Thus, the anode bar gradually dissolves to replenish the silver ions in the solution. The net result is that silver metal has been transferred from the anode to the cathode, in this case the spoon. This process continues until the desired coating thickness is built up on the spoon- usually only a few thousandths of an inch-or until the silver bar has completely dissolved. (2) Given; d=10units R(6,4) and S(2,K) d=sqroot(y2-y1)^2+(x2-x1)^2 10^2=(k-4)^2+(2-6)^2 100=k^2-8k+16+16 k^2-8k+32-100=0 k^2-8k-68=0 k=8+_sqroot(8^2-4*1*-68)/2 k=8+_sqroot(64+272)/2 k=8+_sqroot(64+272)/2 k=8+_sqroot(336)/2 k=8+_18.3/2 k=8-18.3/2 or 8+18.3/2 k=-5.15 or 13.15 (4) Velocity ratio(V.R)=1/sintita 4=1/sintita sintita=1/4 tita=sin^-1(0.25) (7) This is because the speed of sound decreases as temperature increases.On hot day the temperature in high hence the speed decreases while on cold day,the speed increases because temperature is lowered (8) Given;length(l)=2.0m Resistance(R)=3.0ohm Diameter(d)=0.8mm d=0.8*10^-3m Resistivity=? R=el/A A=(pie*d^2)/4 =3.142/4*(0.8*10^-3)^2 A=(3.142*0.64*10^-6)/4 A=0.50*10^-7m^2 A=5*10^-7m^2 3.0=(e*2)/(5*10^-7) e=(15*10^-7)/2 Resistivity(e)=7.5*10^-7nm (5a) Energy is the ability to do work while power is the rate expended (5b) Given mass of man(m)=72kg height(h)=5m time(t)=40s p=mgh/t=energy/time p=(72*10*5)/40 p=90W (12a) -Sugar tongs->third class -Nutcracker->second class -Bottle opener->first class (12b) (i)Archemedes' principle states that a body which is wholly or partially immersed in a fluid ,experiences loss in wheight which is equals to weight of fluid displaced (ii)This is due to the resulting apparent weight of the object in liquid which is less than true weight 12c) Given; mass(m)=500g=0.5kg Force constant(k)=4Nm^-1 i)Period (T)=w=sqroot(k/m) =sqroot(4/0.5) w=sqroot(8) =2.83rad/s w=2*pie*f w=2*pie(1/T) 2.83=(2*3.142)/T T=(2*3.142)/2.83 =2.22s ii)frequencyf=1/T f=1/2.22 =0.45Hz 14a) landa=wavelength x=wave distance v=velocity/speed 14b) i)The eye is a natural optical device while camera is artificial optical device ii)-Both eye and camera are used as optical device -Both eye and camera use lenses 14c) i)Resonance is a phenomenon where by a vibrating body sets another body vibrating both having the same natural frequency ii)Length(L)=45cm=0.45m L=landa/2 0.45=landa/2 landa=0.45*2=0.90m v=f*landa 340=fo*0.90 fo=340//0.90 fo=377.8Hz =================== 15a) i)-its presence gives charge -its presence bring spark -its presence bring light ii)The presence of charge is responsible for moving charges 15b) i)-it is used for radio turning -it is used to reduce spark ii)-Area of over-lap between the plates -Dustance of seperation between the plates 15c) Force(Fxy)=1.13*10^11N (Fzx)=3.60*10^11N i)Resultant force(Fzy)=R R=sqroot(Fxy^2+Fzx^2) R=sqroot (1.13*10^11)^2+(3.60*10^11)^2 R=sqroot(1.28*10^22+12.96*10^22) R=sqroot(14.24*10^22) R=3.78*10^11N ii)tan tita=(3.60*10^11)/(1.13*10^11) =3.19 tita=tan^-1(3.19)=72 [/quote]