# 2006 - WAEC Physics Past Questions and Answers - page 1

1

Which of the following phenomena causes capillary of liquids in tubes of narrow bore?

A

viscosity

B

surface tension

C

osmosis

D

brownian motion

**correct option:**b

2

Which of the following physical quantities are derived? i. Area ii. Thrust iii. Pressure iv. Mass

A

i, ii, iii and iv

B

i, ii and iii only

C

i, ii and iv only

D

i and iii only

**correct option:**b

3

A block of volume 3 x 10

^{5}m^{3}and density 2.5 x 10^{3}kg m^{-3}is suspended from a spring balance with \(\frac{2}{3}\) of its volume immersed in a liquid of density 900 kg m^{-3}. Determine the reading of the spring balance [g = 10ms^{-2}]A

0.18N

B

0.57N

C

0.75n

D

0.93N

**correct option:**b

Volume immersed solid = 3 x 10

= 2 x 10

Mass of liquid displaced = ev

= 2 x 10

Upthrust = 18 x 10

= 7.8 x 10

Mass of solid = ev

= 2.5 x 10

= 7.5 x 10

Weight of solid = 7.5 x 10

Reading = 0.75 - 0.18 = 0.57N

Users' Answers & Comments^{5}x \(\frac{2}{3}\)= 2 x 10

^{5}m^{3}Mass of liquid displaced = ev

= 2 x 10

^{5}x 900 = 18 x 10^{7}kgUpthrust = 18 x 10

^{7}x 10= 7.8 x 10

^{9}NMass of solid = ev

= 2.5 x 10

^{3}x 10^{5}= 7.5 x 10

^{8}Weight of solid = 7.5 x 10

^{8}x10 = 7.8 x 10^{9}Reading = 0.75 - 0.18 = 0.57N

4

A solid body will float in a liquid if its

A

density is less than that of a liquid

B

mass is equal to that of the liquid

C

density is greater than that of the liquid

D

mass is less than that of the liquid

**correct option:**a

5

An object is said to undergo oscillatory motion when it moves

A

in an erratic manner

B

to and fro about a fixed point

C

in a circular path

D

along a continuous path from the starting point

**correct option:**b

6

A body is rotating in a horizontal circle of radius 2.5m with an angular speed of 5 rad s

^{-1}. Calculate the magnitude of the radial acceleration of the bodyA

62.50ms

^{-2}B

31.25ms

^{-2}C

12.50ms

^{-2}D

10.00ms

^{-2}**correct option:**c

\(\alpha = \frac{W_2 - W_1}{t} = \frac{5}{1} = 5 rad\)/s

9 = \(\alpha\)r

= 5 x 2.5 = 12.50m\s

Users' Answers & Comments^{2}9 = \(\alpha\)r

= 5 x 2.5 = 12.50m\s

^{2}7

A moving car of mass 800 kg experiences a frictional force of 200N. If it accelerates 2 ms

^{-2}, calculate the magnitude of the force applied to the carA

600N

B

1000N

C

1600N

D

1800N

8

Uniform speed occurs when there is equal change of

A

distance in equal times

B

displacement in equal times

C

velocity in equal times

D

acceleration in equal times

**correct option:**a

9

A car accelerates uniformly from rest at 5 ms

^{-2}. Determine its speed after 10sA

50.0ms

^{-1}B

25.0ms

^{-1}C

2.0ms

^{-1}D

0.5ms

^{-1}10

Which of the following quantities is a vector?

A

speed

B

distance

C

energy

D

momentum

**correct option:**d