OAU Physics 2012/2013 Past Questions

A body of mass m slides down an inclined plane with a constant velocity. If the angle of the incline is θ, the coefficient of kinetic friction between the body and the plane is

The density of sea water is 1030kg/m³. What is the pressure at a depth of 80m below sea surface? Atmospheric pressure is 1.013 x 10⁵Pa and acceleration due to gravity is 10m/s².

6000J of heat is delivered to 10g of dry ice at 0°C. What is the final temperature if the container has a heat capacity of 20J/k? [specific heat of water = 4200J/kg.k, latent heat of fusion of ice = 3.33 x 10⁵J/kg]

A sample of radioactive substance, whose half — life is 16 days, registers 32 decays per second. Hose long will it take for the rate of decay to reduce to 2 decays per second?

When white light passes through a triangular prism, the emerging rays of light arranged in order of decreasing angle of deviation are

The electric field between two parallel plates is E. A particle of mass m and carrying charge q is released at a point half the distance between the plates. The velocity of the particle t seconds after its release is

The velocity of a 500kg car moving along a straight road, changes from 12m/s to 20m/s in 5 sec. Calculate the average force moving the car

When a 2kg body is at a height 5m above the floor, its velocity is 4m/s. What is its total energy at this height? [acceleration due to gravity = 10m/s²]

An airplane increases its speed from 36km/h to 360km/h in 20.0s. How far does it travel while accelerating?

In the simple circuit shown in fig.l, E is a 24V battery. Calculate the current I

An object is said to be in simple harmonic motion (SHM) if

A wheel and axle is used to raise a weight of 600N with an effort of 300N. If the radii of the wheel and axle are 50cm and 10cm respectively, what is the efficiency of the system?

The term "Viscosity" is used to describe

A particle is in equilibrium under the action of three forces. One force is 40N towards the west and another is 30N towards the south. What is the third force acting on the body?

A hydraulic press works on the principle of transmission of

A cigarette lighter in a car is a resistor that, when activated, is connected across the 12V battery. If the lighter dissipates 33W of power, find the current it delivers to the lighter

A p - n junction can act as

Which of the following is not a thermometer?

Dry air of column length 10cm is trapped by a pellet mercury of length 15cm, with the open end uppermost. When the capillary tube is inverted the length of the air column increased to 25cm while that of mercury remained constant. Calculate the atmospheric pressure (in cm of Hg)

Sound waves were sent out from a source and after being reflected from an obstacle were received by a sensor placed beside the source. If the waves were received 10 seconds after they were sent out, calculate the distance between the source and the obstacle. (speed of sound = 330m/s)

Which of the following is not true about a chemical cell?

Calcium has a work function of 19eV with wavelength of 150nm. Calculate the maximum energy a a photo electron emitted. (1 eV = 1.6 x 10^-19J, h = 6.6 x 10^-34Js)