OAU Physics 2014/2015 Past Questions

Practice each question, then open it to see the full details.

Adeoye moves a distance of 4.0 km from a point, A on a bearing of N30°E to a point Band then a distance of 3.0 km on a bearing of S60°E to a point, C. Calculate Adeoyes resultant displacement from point, A.

A.10km, N60°E
B.5km, N67°E
C.3km, S30°E
D.4km, S60°E

Which of the following statements is true?

A.The unit of mass is Newton (N)
B.Weight of an object is a scalar quantity
C.The weight of an object varies from one place to another
D.The dimensions of weight are M^-2LT^-2

Which of the following is not an example of rotational motion?

A.rotation of electric fan blades
B.movement of car wheels
C.rotation of the earth about its axis
D.movement of a loaded spring about its equilibrium position

An object of mass, 5 kg placed on an inclined plane (which is at an angle of 30° to the horizontal) is attached to a 10 kg mass through a pulley, with the 10 kg hanging vertically. Calculate the acceleration of the mass-system in terms of the acceleration due to gravity, g,if there is no friction between the 5kg mass and the plane.

A.2/5g
B.3/5g
C.1/2g
D.3/2g

Which of the following is not true about the mechanical energy of a system in a conservative field?

A.total energy is zero
B.total energy is the sum of the kinetic energy and the potential energy
C.total energy is equal to the maximum value of kinetic energy
D.total energy is equal to the maximum value of potential energy

Surface tension is the

A.pressure per unit length on either side of the imaginary line drawn on the liquid surface at rest
B.force per unit length on either side of the imaginary line drawn on the liquid surface at rest
C.current per unit length on either side of the imaginary line drawn on the liquid surface at rest
D.area per unit length on either side of the imaginary line drawn on the liquid surface at rest.

A machine has an efficiency of 60 %. If the machine applied a force of 2000 N to overcome a load of 5000N, calculate the velocity ratio of the machine.

A.2.4
B.3.3
C.4.2
D.5.5

Which of the following statements is true about the hydrostatic pressure? (i) Pressure increases with height (ii) Pressure is independent of the shape and volume of the vessel (iii) Pressure is the same at all points on the same horizontal plane in a fluid (iv) Pressure is independent of the surface area incontact

A.(i), (ii), (iii) and (iv)
B.(i), (ii), and(iii) only
C.(ii), (iii) and (iv) only
D.(i), (ii), and (iv) only

The resistance of a platinum resistance thermometer is 160.5Ω at steam point and 60.5Ω at the melting point of Ice. Calculate the resistance of the thermometer at 70°C

A.160.5Ω
B.165.5Ω
C.130.5Ω
D.170.5Ω

The wall separating a Bakery Oven and its environment is of height, 10m; breadth, 10m; and Thickness, 25 cm. If the rate of heat exchange between the Oven and its environment is 1000 watt and the temperature of the environment is 27°C, calculate the temperature of the Oven, given that the Coefficient of thermal conductivity of the wall is 0.054Wm^-1K^-1

A.27.3°C
B.-40.2°C
C.40.2°C
D.73.3°C

Which of the following is not an application of expansion of solids?

A.Rivets
B.Bimetal strips
C.Fitting of wheels on rims in Railway Coaches
D.Regelation

Which of the following is true about melting point of a liquid?

A.The presence of dissolved impurities increases the melting of a pure solid
B.An increase in pressure decreases the melting point of a substance that contracts in volume on freezing , more than the one that expands in volume
C.The melting point is not the same as the solidification of a substance.
D.The presence of the dissolved impurities does not change the melting point of a pure solid.

A boy preparing to have his bath mixed 50 kg of water at a temperature of 80°C with 70kg of water at a temperature of 20°C. What is the temperature of the water mixture?

A.45°C
B.75°C
C.65°C
D.35°C

Which of the following is not a property of sound wave?

A.Reflection
B.Diffraction
C.Polarization
D.Refraction

A pin at the bottom of a beaker filled with water appeared to be elevated when viewed from the top of the beaker. Calculate the displacement of the pin from the bottom of the beaker, it the beaker is filled to 8.0cm height and the refractive index of water is 4/3.

A.6.0cm
B.2.0 cm
C.3.0 cm
D.4.0 cm

A boy stands at a distance, x from a wall. When he shouted, the echo was heard 2 seconds later. Calculate the distance from the wall, given that the speed of light is 330 m/s.

A.500m
B.340m
C.250m
D.495m

Ina 60°prism of refractive index, 1.5, calculate the angle of minimum deviation when light is refracted through the prism.

A.40.2°
B.37.5°
C.37.2°
D.40.5°.

Calculate the resultant capacitance of the capacitor network, if each capacitor has a capacitance of 2µF.

A.2.0µF
B.1.0µF
C.2.5µF
D.2.3µF

A cell of e.m.f 4.0 V is connected in series to two resistors 2Ω and 4Ω, which are connected in parallel. Calculate the current which flows through the 4Ω resistor.

A.1.0A
B.2.0A
C.3.0A
D.4.0A

A step-down transformer is energized by a 220 V a.c supply and supplied a current of 10A to the secondary winding. Calculate the current which flows through the primary winding if the ratio of the primary winding to secondary winding is 10:3.

A.10A
B.3A
C.4A
D.5A

All the following properties are characteristic. of X-rays except

A.they have short wavelength
B.they have no charge
C.they are electromagnetic in nature
D.they do not affect photographic plates

$↖{238}↙{92}U$ → $↖{234}↙{90}B$ + X
What particle is emitted in radioactive decay process shown above?

A.β particle
B.X-ray
C.α particle
D.γ ray