OAU Physics 2011/2012 Past Questions

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

Which of the following phenomena cannot be explained by the molecular theory of matter?

A.evaporation
B.expansion
C.conduction
D.radiation

The most likely measurement of length of an object using a vernier caliper is:

A.3.0 cm
B.3.3 cm
C.3.33 cm
D.3.333cm

If 21 g of alcohol of density 0.7 gcm^-3 is mixed with 10 g of water, what would be the density of the resulting mixture?

A.780 gcm^-3
B.0.78 gcm^-3
C.30 gcm^-3
D.10 gcm^-3

For a particle having an x coordinate that varies in time according to the expressionx = 4t - 2t². The instantaneous velocity for of the particle at t = 2.5 s is:

A.12 m/s
B.6 m/s
C.0 m/s
D.10 m/s

A long jumper leaves the ground at an angle of 20° above the horizontal and at a speed of 11 m/s. llos far does it jumps in the horizontal direction?

A.0.384m
B.7.94 m
C.8.45 m
D.0m

A mass of 0.5 kg is attached to one end of a helical spring and produces an extension of 2.5 cm. The mass now set into vertical oscillation of amplitude 10 mm. The period of oscillation is: (g = 10 m/s²)

A.033 s
B.100 s
C.200 s
D.280 s

A boat is passing under a bridge. The deck of the boat is 15m below the bridge. A small package is to be dropped from the bridge onto the deck of the boat when the boat is 25m from just below the drop point. What (boat) speed is necessary to have the package land in the boat? (g = 9.8 m/s^2)

A.17 m/s
B.14 m/s
C.1.7 m/s
D.4.9 m/s

An 0.60kg rubber stopper is whirled in a horizontal circle of 0.80m radius at a rate of 3.0 revolutions per second. What is the tension in the string?

A.14 N
B.80 N
C.170 N
D.24 N

An automobile is traveling at 60km/hr. Calculate the angular velocity of the 0.35m radius wheels.

A.6.67 rad/s
B.47.6 rad/s
C.21 rad/s
D.171.4 rad/s

An air bubble at the bottom of a lake has a volume of 20cm^3 pressure of 4.9Pa, and temperature 4°C. the bubble rises to the surface where the temperature is 20°C and the pressure 1.0 Pa. Find the volume as the bubble reaches the surface. (take 1 atm = 1.0 x l0⁵ N/m².

A.124cm³
B.319cm³
C.60cm³
D.104cm³

A as at constant pressure of 4.0 x 10⁵ Pa is cooled so that its volume decreases form 1.6m³ to 1.2m³. What work is performed by the gas?

A.6.4 x 10⁵J
B.3.2 x 10⁵ J
C.1.6 x 10⁵ J
D.0.4 x 10⁵J

Highly polished silvery surfaces are:

A.poor absorbers but good emitter of radiation
B.Good absorbers and good emitters of radiation
C.poor emitters but good reflectors of radiation
D.Poor emitters and poor reflectors of radiation

An 0.040kg string 0.80m long is stretched and vibrated in a fundamental mode with a frequency of 40Hz. What is the speed (of propagation) of the wave and the tension in the string?

A.64 m/s
B.340 m/s
C.32 m/s
D.128 m/s

What is the total power output of a source with intensity 0.050 W/m2 at a distance of 3.0m from the source?

A.112W
B.5.6 W
C.15 W
D.30 W

The superposition of two or more waves to produce a maximum or zero effect at a point is known as:

A.reflection
B.refraction
C.diffraction
D.interference

The acceleration due to gravity

A.increases with increasing altitude
B.decreases with increasing altitude
C.increases with increase in increase in the square of the altitude
D.is not affected by the altitude

Which of the following about electrolysis is false?

A.liquid that conduct electricity and are split up chemically by the current are electrolyzed
B.the current is brought into the electrolyte by the anode.
C.the current is taken away from the electrolyte by the cathode
D.the container which holds the electrolyte and the electrode is the voltmeter

Which of the following is not true about the properties of x-rays?

A.they are not deflected by magnetic or electric field
B.they ionized a gas, making it a conductor
C.they are massive
D.the' have high penetrating power

A transformer is connected to a 240 V supply. The primary coil has 40 turns, and the secondary is found to be 960V. What is the ratio of the number of turns of the primary coil to the number of turns it the secondary coil?

A.1 : 4
B.4 : 1
C.1 : 6
D.6 : 1

Which of the following is not true about an object that is projected upwards at angle θ.

A.the velocity is maximum at the maximum height
B.the acceleration along the horizontal direction is zero
C.the maximum range (Rmax) for an object moving with speed u is given by u^2/g
D.the time it takes to get the maximum height is equal to the time it takes to come back to the point o, projection.

When three coplanar non-parallel forces are in equilibrium. i. they can be represented in magnitude and direction by the three sides of a triangle taken in order. ii. The lines of action meet at a point iii. The magnitude of any one force equals the magnitude of the resultant of the other two forces. iv. Any one force is the equivalent of the other two. Which of the following statements above are correct?

A.i and iii only
B.i and ii only
C.i, ii, iii, and iv
D.none of them

Which of the following statements is not TRUE about a body performing simple harmonic motion?

A.the linear speed is the product of the angular speed and the radius or amplitude
B.the linear acceleration is the product of the square of the angular speed and the displacement
C.frequency is the number of complete revolution per second made by a vibrating body
D.the SI unit of amplitude is Hertz (Hz)

If the force of gravity on an object of mass M, the gravitational field strength, g, is given by the following equation.

A.g = √MF
B.g = MF
C.g = M√F
D.g = F/M