Physics — 2007

Which of the following observations is not an effect of surface tension?

Which of the following physical quantities is correctly paired with it's corresponding S.I unit?

A liquid of volume 2.00 m3 and density 1.00 x 103 is mixed with 3.00 m3 of another liquid of density 8.00 x 103kg m-3. Calculate the density of the mixture [Assuming there is no chemical reaction]

Which of the following statements about solid friction are correct? It i. is a force ii. occurs between the surfaces of two bodies in contact iii. depends on the area in contact

A mass of mass m, experiences a viscous drag, F and an upthrust, U as he descends towards the ground at a steady velocity, Using a parachute. If the acceleration of free fall is g, which of the following expressions is correct?

a body moving at a constant speed accelerates when it is in

An object of mass 2 kg moves with a uniform speed of 10ms-1 for 5s along a straight path. Determine the magnitude of its acceleration

The term rectilinear acceleration means the rate of increase of

A body moving with an initial velocity U accelerates until it attains a velocity of V within a time t. The distance, s covered by the body is given by the expressions

A body accelerates uniformly from rest at 2ms -2 . Calculate the magnitude of its velocity after travelling 9m

A swinging pendulum between the rest position and its maximum displacement possesses

A block of mass 4.0kg causes a spiral spring to extend by 0.16m from its unstretched position. The block is removed and another body of mass 0.50kg is hung from the same spiral spring. If the spring is then stretched and released, what is the angular frequency of the subsequent motion? [g = 10 ms -2 ]

An external force of magnitude 100N acts on a particle of mass 0.15kg for 0.03s. Calculate the change in the speed of the particle

A car of mass 800kg moves from rest on a horizontal track and travels 60m in 20s with uniform acceleration. Assuming there were no frictional forces, calculate the accelerating force

A plane inclined at 30 o to the horizontal has an efficiency of 50%. Calculate the force parallel to the plane required to push a load of 120N uniformly upn the plane

Mechanical energy can be either

Which of the following surfaces will radiate heat energy best?

The ice and steam point on a mercury-in-glass thermometer are 10cm and 30cm respectively. Calculate the temperature in decree Celsius when the mercury meniscus is the 14cm mark

Which of the following statements distinguishes thermal conduction for convection? i. Conduction requires a material medium while convection does not ii. In convection, there is actual motion of hot material, while in conduction, molecules molecules vibrates faster about their mean positions iii. Conduction takes place in solids while convection takes place in fluids.

A cube made of metal of linear expansivity \(\alpha\) is heated through a temperature \(\theta\). If the initial volume of the cube is V o , the correct expression for the increase in volume of the cube is

A relative density bottle of volume 50cm 3 is completely filled with a liquid at 30 o C. It is then heated to 80 o C such that 0.75cm 3 of the liquid is expelled. Calculate the apparent cubic expansivity of the liquid.

A body of mass 200g and specific heat capacity 0.4Jg -1 k -1 cools from 37 o C to 31 o C. Calculate the quantity of the heat released by the body.

According to the kinetic theory of gasses, which of the following property of a gas can be affected by the collision of the gas molecule with the walls of the container?

The pressure of a fixed mass of an ideal gas at 27°C is 3 pa. The gas is heated at a constant volume until its pressure is 5 pa. Determine the new temperature of the gas.

Which of the following wave is electromagnetic?

The distance between two points P and Q, along a wave is 0.05m. If the wave length of the wave is 0.10m, determine the phase angle between P and Q in radians

Which of the following phenomena is not a direct consequence of rectilinear propagation of light?

An object is placed 10cm in front of a plane mirror. If it is moved 8cm away father away from the mirror, determine the distance of the final image from the mirror

In which of the following piece of apparatus is the radius of curvature equal to twice the focal length?

When an object is placed at the centre of curvature of a concave mirror, its image is formed at

A rectangular glass prism of thickness d and absolute refractive index n is placed on a point object which is viewed vertically downward from above the prism. Which of the following expressions correctly defines the apparent upward displacement of the object?

Which of the following factors can affect the speed of sound in air? i. The temperature of the surrounding ii. The direction of the wind iii. The pitch of the sound.

A sounding tuning fork is brought near the open end of a pipe containing air and the loudness of the sound is observed to increase. This observation is due to

Which of the following statements about sound wave is not correct? Sound waves can be

A dry plastic comb used in combing hair was found to attract pieces of paper and dust. The most probable explanation for this phenomenon is that the comb has been given

Which of the following statements is correct about resonance? Resonance occurs when a body

Which of the following components is used for storing electric charges?

Which of the following operations does not represent an action of a force field?

A bulb marked 240V, 40W is used for 30 minutes. Calculate the heat generated

Five 80-W and three 100W are run for 8 hours. If the cost of energy is N5.00 per unit, calculate the cost of running the lamp. [1 unit = 1 kWh]

Which of the following electromagnetic wave can be detected by its heating effect?

If a gas is excited by high voltage to produce a discharge and the light is examined in a spectrometer

The number of protons in an element increased by one after a radioactive decay. The element must have decay by emitting

In a nuclear reactor, chain reactions result from the release of

The correct sequence of energy transformation in the operation of an x-ray tube is i. X-rays ii. Kinetic energy of thermo electrons iii. Potential energy of the target atoms iv. Heat energy of the emitted electrons

There is always an uncertainty involved in any attempt to measure the position and momentum of an electron simultaneously. This statement is known as the

The diagram above illustrates three forces acting on an object at point O. If the object is in equilibrium, determine the magnitude of the force P.

Calculate the effective resistance between P and Q in the diagram above