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Physico- obj
1 CCBBCBDBCD
11 DACADCAADB
21 BACBBBDDBD
31 DDDBDABABA
41 BCAADABCDC 1)
– IMPULSE = MLT^-1
– ACCELATION = V/T = LT^1 / T
– WORK = ML^2 T^-2
(Note: This symbols ^ means Raise to power)
2)
V/u = sin θ
Vy = u sin θ
Vy = 20 sin 40
Vy =12.86m/s
(3)
– smoke
– aerosol
– dust particle
(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
5)
– For launching astronauts into the space
– For launching satellite
– For Scientific research
– For Fireword
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
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 = 2×3.142×5
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)
9a)
i)Foundamental interval: is the value arbitrarily assigned to the difference in temperature between two fixed points (such as the ice point and steam point) on a temperature scale, in order to define the scale.
ii)Thermal equilibrium: is a higher temperature object which is in contact with
a lower temperature object that transfers heat to the lower temperature
object. The objects will approach the same temperature, and in the
absence of loss to other objects, they will then maintain a constant
temperature.
9b) Uses of hydraulic press:
– It is used in metal forming operations
– For moulding
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
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
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
