Recent questions tagged 2011

The time period of a simple harmonic motion is 8s. At t=0 , it is at its equilibrium position. The ratio of distances traversed by it in the first and second seconds is :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

A body is projected vertically upwards from the surface of the earth with a velocity equal to $\large\frac{3}{4}$th escape velocity of earth. If 'R' is the radius of earth, the maximum height attained by the body is :

asked Nov 2, 2013 by thanvigandhi_1

2 answers

A wheel of radius 0.5 m rolls without sliding on a horizontal surface, starting from rest, the wheel moves with constant acceleration $6\: rad/s^2$ . The distance travelled by the centre of the wheel from $ t = 0 \: to \: t=3s$ is :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

Two circular rings of equal mass (m) and radius (r) are placed side by side, touching each other. The moment of inertia of the system about tangential axis in the plane of system passing through point of contact of the rings is :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

A uniform chain of length 'l' is placed on a rough table, with its length $ \large\frac{l}{n} ( n > 1)$ hanging over the edge of the table. If the chain just begins to slide off the table by itself, the coefficient of friction between the chain and the table is :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

A uniform metal disc of diameter 24 cm is taken and out of it a disc of diameter 8 cm is cut off from the right side end. The centre of mass of the remaining part will be at :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

A shell is fired from a cannon with a velocity 'v' at an angle $ '\theta'$ with the horizontal. At the highest point in its path it explodes into two pieces of equal masses. One of the pieces retraces its path and reaches the cannon. Then the velocity of the other piece immediately after collision is :

asked Nov 2, 2013 by thanvigandhi_1

1 answer

A bullet is fired normally towards an immovable wooden block. It loses 25% of its kinetic energy in penetrating through a thickness 'x' of the plank. The total thickness penetrated by the bullet into the block is :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

The acceleration of 3 kg mass in figure shown is ( assume $g = 10 m/s^2 )$ :

asked Nov 1, 2013 by thanvigandhi_1

0 answers

A ball is dropped into a well. The water level in the well is at a depth 'h' below the top. If the speed of sound is V, then after what time the splash of sound is heard?

asked Nov 1, 2013 by thanvigandhi_1

2 answers

Two vectors are $( \overrightarrow A + \overrightarrow B)$ and $( \overrightarrow A - \overrightarrow B)$. The angle between their resultant vector and $ \overrightarrow A $ is :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

Match the following physical quantities with their respective dimensional formula :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

A magnet of length 10 cm and magnetic moment $1 Am^2$ is placed along the side AB of an equilateral triangle ABC. If the length of sides AB is 10 cm, the magnetic induction at point C is :

asked Nov 1, 2013 by thanvigandhi_1

2 answers

Two polarizers have their axis inclined at $ 45^{\circ}$ to each other. If unpolarized light of intensity $I_{\circ}$ is incident on the first polarizer , then the intensity transmitted light through second polarizer is :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

When a light of wavelength 4000 A in vacuum travels through the same thickness in diamond and water separately, the difference in the number of waves is 200. Find the thickness, if refractive indices of diamond and water are $ \large\frac{5}{2}\: and \: \large\frac{4}{3}$ respectively :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

A thin bi-convex lens of focal length 20 cm is made of glass of refractive index 1.5, when it is dipped in a liquid of refractive index $ \large\frac{9}{8} $, it acts as :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

A water film is formed on a glass-block. A light ray is incident on water film from air at an angle $60^{\circ}$ with the normal. The angle of incidence on glass slabs is $ \bigg[ \: given\: \mu_g = 1.5,\: \mu_W = \large\frac{4}{3} \bigg] $ :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

Two identical flutes produce fundamental notes of frequency 300 Hz at $27^{\circ}C$. If the temperature of the air in one of the flutes is increased to $31^{\circ}C$, the number of beats heard per seconds will be :

asked Nov 1, 2013 by thanvigandhi_1

1 answer

A source of sound producing wavelength 50 cm is moving away from a stationary observer with $ \large\frac{1}{5}th$ speed of sound. Then what is the wavelength of sound heard by the observer?

asked Nov 1, 2013 by thanvigandhi_1

1 answer

The temperature of a perfect black body is $727^{\circ}C$ and its area is $0.1\: m^2$. If Stefan's constant is $ 5.67 \times 10^{-8} W/m^2K^4$, then heat radiated by it in $0.3$ minutes is :

asked Nov 1, 2013 by thanvigandhi_1

1 answer