2012 - WAEC Physics Past Questions and Answers - page 1
1
The derived unit of pressure can be expressed as
A
kgms-2
B
kg m-1s-2
C
kg m-2s-2
D
kg m-1s2
correct option: b
Users' Answers & Comments2
The diagram above illustrates trapped air in a syringe placed in water that is gradually heated. It is observed that the piston rises as the temperature of the water rises. Which of the following statements explains this observation?
A
frequency of collision of trapped air molecules with walls of the syringe is more
B
molecules of trapped air expands more
C
speed of the trapped air molecules decreases
D
number of molecules of trapped air increases
correct option: b
Users' Answers & Comments3
Which of the following devices is used to determine the relative density of an acid?
A
manometer
B
hydrometer
C
hypsometer
D
hygrometer
correct option: b
Users' Answers & Comments4
A block of wood of density 0.6 gcm-3, weighing 3.06N in air, floats freely in a liquid of density 0.9 gcm-3. Calculate volume of the portion immersed (g = 10ms-2)
A
510cm3
B
340cm3
C
254cm3
D
170cm3
correct option: b
V = \(\frac{M}{D}\)
= \(\frac{3.06}{10} \times \frac{1000}{0.9} = 340\)
Users' Answers & Comments= \(\frac{3.06}{10} \times \frac{1000}{0.9} = 340\)
5
A metal ball of weight W falls through a column of glycerine of viscosity V. If the ball experiences an upthrust U and terminal velocity is attained is attained, then
A
W > U + V
B
W = U + V
C
W = U - V
D
W < U + V
correct option: b
Users' Answers & Comments6
The movement of fluid up or down a narrow tube is
A
osmosis
B
brownian motion
C
capillarity
D
diffusion
correct option: c
Users' Answers & Comments7
Which of the following substances is the most volatile at room temperature?
A
water
B
diesel
C
petrol
D
kerosine
correct option: c
Users' Answers & Comments8
a bird flies at 10ms-1 for 3s, 15ms-1 for 3s and 20 ms-1 for 4s. Calculate the bird's average speed
A
4.5 ms-1
B
15.0 ms-1
C
15.5 ms-1
D
51.7 ms-1
correct option: c
A.V. speed = \(\frac{3 \times 15 + 3 \times 20 + 4 \times 20}{3 + 3 + 4}\)
= 15.5 ms-1
Users' Answers & Comments= 15.5 ms-1
9
The time of flight for a projectile motion is given by the expression
A
\(\frac{U sin \theta}{g}\)
B
\(\frac{U sin \theta}{2g}\)
C
\(\frac{2U sin \theta}{g}\)
D
\(\frac{U sin 2\theta}{g}\)
correct option: c
Users' Answers & Comments10
An object is dropped from the top of a tower. If it takes 4s for it to reach the ground, calculate the height of the tower.(g = 10 ms-2, ignore air resistance)
A
20m
B
40m
C
80m
D
160m
correct option: c
H = \(\frac{1}{2} gt^2\)
\(\frac{1}{2} \times 10 \times 4^2 = 80\)
Users' Answers & Comments\(\frac{1}{2} \times 10 \times 4^2 = 80\)