Physics — 2011

Which of the following statements is not correct?

The density P of a spherical ball of diameter d and mass m is given by

A metal rod of density 7000 kgm -3 and cross-sectional area of 0.001257m 2 has a mass of 1.76kg. Calculate its length.

The pressure in a liquid

The property of a fluid that is used to determine its suitability as a lubricant is its

The area under a velocity-time graph represents

In the absence of gravitational force, the weight of the body is

Which of the following propeties is not considered in choosing mercury as a thermomemetric liquid?

A stone of mass 300g is released from rest from the top of a bulding of height 100m. Determine the kinetic energy gained by the stone when it is a quarter way down from the point of release.[g = 10 ms -2 ]

A body of mass 120g placed at the 10cm mark on a uniform metre rule makes the rule settle horizontally on a fulcrum places at 35cm mark. Calculate the mass of the rule

Two simple pendulum A and B of equal lengths and of masses 5g and 20g respectively are located in the same environment. The periods TA and TB of their respective oscillations are related by the equations

An object of mass 5.0 kg moves with a velocity of 10ms -1 . Calculate its momentum.

A coin is pushed from the edge of a laboratory bench with a horizontal velocity of 15.0 ms -1 . If the height of the bench from the floor is 1.5m, calculate the distance from the foot of the bench to the point of impact with the floor [g = 10ms -2 ]

Which of the following statements correctly defines a simple machine? A device

The radius of a wheel is 30.0 cm and that of its axle is 6.0cm. Calculate the effort required to lift a load of 120.0N using this machine. Assuming 100% efficiency

A hypsometer is used for determining

Which of the following equations shows how how the linear expansivity (\(\alpha\)) and the cubic expansivity (\(\gamma\)) of a material are related?

Which of the following statements about anomalous expansion of water are correct? i. There is contraction between 0 o C and 4 o C. ii. There is expansion between 0 o C and 100 o C. iii. The volume is minimum at 4 o C. iv. The volume is maximum at 4 o C

Which of the following assumptions is not valid for an ideal gas ?

A body is pulled over a distance of 500m by a force of 20N. If the power developed is o.4 kW, calculate the time interval during which the force is applied

A metal of mass 200g at a temperature of 100 o C is placed in 100g of water at 25 o C in a container of negligible heat capacity. If the final steady temperature is 30 o C, calculate the specific heat capacity of the metal. [specific heat capacity of the water is 4200 Jkg -1 K -1 ]

Ether produces a cooling effect when it is poured on the hand because it has

Which of the following statements about the image formed by a plane mirror is not correct?

The image formed by a convex mirror is always

A ray undergoes a minimum deviation at 40 o when it is incident on equilateral triangular glass prism. Calculate the refractive index of the prism

Total internal reflection occurs in an optical prism when light rays

The speed of light in a certain medium is V while its speed in a vacuum is C. The absolute refractive index of the medium is

An object is placed 20.0cm in front of a converging lens of focal length 15.0cm. Calculate its image distance

Presbyopia is a defect of the eye resulting from

The focal length of the eye-piece of an astronomical telescope is f 1 , while the focal length of the object is f 2 . Fro normal adjustment, the angular magnification is given by

two sound waves have frequencies of 12Hz and 10Hz. Calculate their beats period

The main difference between echo and reverberation is that

Which of the following statements about the electromagnetic waves is correct?

The correct relationship between "G" and "g" in a gravitational field is given by the equation (Where the symbols have their usual meanings)

The capacitance of a parallel-plate capacitor

When the pointed end of an uncharged optical pin is brought near the cap cf a positively charged electroscope, it is observed that the gold

Which of the following substances does not conduct electricity?

The unit of capacitance is

An ammeter with a full scale deflection of 10mA has an internal resistance 0.5\(\Omega\). calculate the resistance of the shunt required to adapt it to read up to 3A

The resistivity, \(\mathit{P}\), of a material of length l, cross-sectional area A, resistance R, is given by the equation

A wire of length 30cm is moved with a speed of 2ms -1 at right angles to a magnetic field of flux density 0.4T. calculate the emf induced in the wire

Which of the following practices will lead to losses in electrical power transmission?

For photoelectric emission, the threshold frequency is the

Which of the following properties is not applicable to X-rays? They

Uranium-234 disintegrated to form Thorium-230 by emitting

The change in mass of fuel during a nuclear reaction is 2.0 x 10 -27 kg. Calculate the amount of energy released. (Speed of light = 2.0 x 10 8 ms -1 )

Nuclear fusion is not used as a source of enegy because

Using the circuit diagram above. Calculate the total charge in the circuit

Using the circuit diagram above. Calculate the potential difference across the capacitors in parallel