Question Library — KalmiPrep by Kalmitech

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

The product PV where P is pressure and V is volume has the same unit as

A

power

B

work

C

acceleration

D

impulse

E

force

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

The set-up illustrated above shows a capillary tube of uniform cross-sectional area in two different arrangements. Using the data in the diagrams. Calculate the pressure of the atmosphere

Attached Figure / Diagram

A

76cm of Hg

B

75cm of Hg

C

74cm of Hg

D

60cm of Hg

E

45cm of Hg

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

Two forces, whose resultant is 100N are perpendicular to each other. If one of them makes an angle of 60o with the resultant, calculate the magnitude. (Sin 60o = 0.8660, Cos 60o = 0.500)

A

200.0N

B

173.2N

C

115.5N

D

86.6N

E

50.0N

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

The graph above shows the expansion of water as the temperature increases from 0oC. Which of the following deductions from the graph are true? i. Water has its maximum density at Q. ii. The volume of water is greater at 0oC than at 4oC. iii. The volume of water decreases uniformly when cooled from 100oC. iv. When water solidifies, its volume increases

Attached Figure / Diagram

A

i and ii only

B

i and iii only

C

ii and iii only

D

i, ii and iii only

E

i, ii and iv only

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

A man standing 300m away from the wall sounds a whistle. The echo from the wall reaches him 1.8sec. later, calculate the velocity of sound in air

A

540.0ms-1

B

333.3ms-1

C

270.0ms-1

D

166.7ms-1

E

83.3ms-1

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

A particle of charge q and mass m moving with a velocity v enters a uniform magnetic field b in the direction of the field. The force on the particle is

A

qvB

B

mqvB/m

C

mvB/q

D

O

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

The unit of stress is

A

Nm

B

N

C

Nm-2

D

Nm2

E

Nm1

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

Which of the following statements above viscosity are correct? when a ball falls through a viscous liquid i. viscosity opposes the gravitational force on the ball. ii. viscosity opposes the upthrust on the ball. iii. viscosity is in the same direction as the upthrust on the ball. iv. as the ball falls faster the more viscous the liquid is

A

i and iii only

B

i and ii only

C

ii and iv only

D

iii and iv only

E

i, ii and iv only

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

plane as 63cm of HG while a ground observer records a reading of 75cm of Hg with his barometer. assuming that the density of air is constant, calculate the height of the plane above the ground. (Take the relative densities of air and mecury as 0.00136 and 13.6 respectively

A

120m

B

138m

C

1200m

D

274m

E

120,000m

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

Two capacitors C1 and C2 are connected as shown in the diagram. The capacitance C2 is twice C1 when the key is opened the energy stored up in C1 is W. If the key is later closed and the system is allowed to attain electrical equilibrium, the total energy stored in the system will be

Attached Figure / Diagram

A

\(\frac{1}{2}\)W

B

\(\frac{2}{3}\)W

C

W

D

2w

E

3W

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

Which of the following is stored by dry Leclanche cell?

A

chemical energy

B

nuclear energy

C

solar energy

D

heat energy

E

electrical energy

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

A 90W immersion heater is used to supply energy for 5 minutes. The energy supplied is used to completely melt 160g of a solid at its melting point. Calculate the specific latent heat of the solid.

A

2.81jg-1

B

6.25Jg-1

C

8.89Jg-1

D

168.75Jg-1

E

5333.33Jg-1

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

When a metal surface is irradiated, photoelectrons may be ejected from the metal. The kinetic energy of the ejected electrons depends on the

A

sorce of the radiation

B

intensity of the radiation

C

detection device for the electrons

D

amplitude of the radiation

E

frequency of the radiation

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

An electron charge 1.6 x 10-19C is accelerated in vacuum from rest at zero volt towards a plate at 40k V. Calculate the kinetic energy of the electron

A

4.0 x 10-26J

B

4.0 x 10-21J

C

6.4 x 10-20J

D

3.2 x 10-15J

E

2.5 x 10-20J

medium Difficulty

Physics WAEC / WASSCE 1991 Mechanics and Properties of Matter

The work function of a metal is 4.65ev and the metal is illuminated with a radiation of 6.86ev. What is the kinetic energy of the electrons ejected from the surface of the metal?

A

1.48ev

B

2.21ev

C

4.42ev

D

5.75ev

E

11.51ev

medium Difficulty