WAEC 2021 Physics Practical Answers (Alternative B) are now out. To get the answers, simply buy MTN rexharge card of N300 and send the pin and subject oaid for to 09067385574

See Physics Practical Answers for Alternative A

1)
TABULATE:
i:1,2,3,4,5,
L(cm): 80.00,70.00,60.00,50.00,40.00
t1(s): 17.87,16.22,16.09,14.08,13.28
t2(2): 17.56,16.46,15.09,14.77,13.36
t(s)mean: 17.715,16.340,15.590,14.425,13.320
T(t/10)s: 1.7715,1.6340,1.5590,1.4425,1.3320
LogT(s): 0.2483,0.2133,0.1928,0.1591,0.1212
Log L(cm): 1.9031,1.8451,1.7782,1.6990,1.6021
Log T10^-2(s): 24.83,21.33,19.28,15.91,12.12
Log L10^-1(cm): 19.031,18.451,17.782,16.990,16.021
SLOPE(s) = (LogT210^-2 – LogT110^-2)(/Log L2 10^-1 – LogL110^-1) = (21.33-12.12(s))10^-2/(18.50-16.02(cm)10^-1)
=3.714*10^-1
=0.3714cm^-1

1axi)
i) I ensured supports of pendula were rigged
ii)I avoided parallax error on meter rule/stop watch
1bi) simple harmonic motion is the motion of a body whose acceleration is always direct towards a fixed point and is proportional to the displacement from the fixed points
1bii)
T=1.2secs
Log 1.2=0.079
0079 shown on graph with corresponding Log L read L correctly determined

3a)
TABULATE:
x(cm):10,20,30,40,50,60
V(v):0.65,0.75,1.00,1.20,1.45,1.55
I(A):0.20,0.30,0.35,0.40,0.45,0.55
LogV(v):-0.187,-0.125,0.000,0.079,0.161,0.190
LogI(ohm):-0.699,-0.523,-0.456,-0.396,-0.391,-0.360
SLOPE(s):=( LogI2-LOgI1)/(LogV2-LogV1)
=-0.2-(-0.7)/0.3-(-0.2)
=0.5/0.5
=1AV^-1
3axi)
i) I ensured clean/tight terminals
ii)I opened key when reading was taken
3bi)
i)brightness of the bulb increases
ii)voltage/current through the bulb increases
3bii)
i)diode
ii)transistor

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