2016 WAEC Physics practical Question And Theory Answers

PHYSICS PRACTICAL Answers
1( a )
V (cm )= 10 . 0, 15 . 0 , 20 . 0 , 25 . 0 , 30 . 0, 35 . 0
U (cm )= 47 . 0, 48 . 5 , 50 . 0 , 51 . 5 , 53 . 0 , 54 . 5 respectively
Precautions
i I avoided drought to prevent swinging of the mass Q
ii I avoided parallax error in reading the metre rule
iii I avoided that the mass did not rest on the table

1b i Moment of a force about a point
The moment of a force about a point O is defined as the
vector product (cross product)
Mo = r × F
where r = xi + yj + zk is the radius vector (position vector )
drawn from O to the point of application A of the force F ,
and F = Fx + Fy + Fz is the force vector acting on A .

OR


1b i Moment of a force about a point
The moment of a force about a point O is defined as the
vector product (cross product)
Mo= r × F
where r = xi + yj + zk is the radius vector (position vector)
drawn from O to the point of application A of the force F ,
and F = Fx + Fy + Fz is the force vector acting on A.

1 b(ii) (a) The principle of moment states that if a body is in
equilibrium the the sum of the clockwise turning moments
acting upon it about any point equals the sum of the
anticlockwise turning moment about the same point.
(b) The term equilibrium meabs that when a body acted on
by several forces and it does not accelerate or rotate, it is
said to be at equilibrium.

2bi) Heat Capacity: is the amount of heat required to
change its temperature by one degree , and has units of
energy per
degree .

3a]
TABULATE
S/N-E(v)-V(v)-I(A)-V^-1(v^-1)-I^-1(A^-1)
1-1.50-0.80-0.40-1.250-2.500
2-3.00-1.40-0.70-0.714-1.429
3-4.50-2.00-1.00-0.500-1.000
4-6.00-2.50-1.20-0.400-0.833
5-7.50-3.20-1.50-0.313-0.667

Precautions
-I tightened all the wires tightly together
-I ensured clean terminals
-I avoided zero error on the ammeter used

3bi)
-By using electric cells
-By using electrostatic method
3bii)
For parallel connection=1/R=1/R+1/R
2Rt=R
Rt=R/2ohm
Total=(R/2)+2
4=(R/2)+2
4=(R+4)/2
8=R+4
8-4=R
R=4ohm