Recent questions tagged class11

A train has to negotiate a curve of radius $200\;m$ . By how much should the outer rails be raised with respect to the inner rails for a speed of $36\;km\;h^{-1}$. The distance between the rails is $ 1.5\;m$ Take $g=10 \;m /s^2$

asked Aug 26, 2014 by meena.p

1 answer

A car moves at a speed of $36 \;km\;h^{-1}$ on a level road, The coefficient of fraction between the tyres and the road is $0.8 $. The car negotiates a curve of radius R. If $g =10 ms^2$ the car will skid (or slip) while negotiating the curve if value of R is

asked Aug 26, 2014 by meena.p

1 answer

A particle of mass m moves in a straight line with its velocity varying with distance travelled according to the equation $v=a\sqrt {x}$ , where a is a constant. What is the total work done by all the forces during a displacement from x = 0 to x = d?

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A block of mass 1.6 kg is attached to a horizontal spring that has a force constant of $1.0 \times 10^3 N/m$. The spring is compressed 2.0 cm and is then released from rest. Calculate the speed of the block as it passes through the equilibrium position if a constant friction force of 4 N retards its motion from the moment it is released

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A block of mass 1.6 kg is attached to a horizontal spring that has a force constant of $1.0 \times 10^3 N/m$. The spring is compressed 2.0 cm and is then released from rest. Calculate the speed of the block as it passes through the equilibrium position $x= 0$ if the surface is frictionless.

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A 2 Kg wood block is on a level board and held against a spring of spring constant k=100 N/m which has been compressed .1 m. The block is released and pushed horizontally across the board. The coefficient of friction between the block and the board is $\mu_k = .2$. Find the velocity of the block just as it leaves the spring.

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A spring with a spring constant of 250 N/m has a length of 0.5 meters at rest. What magnitude of force is needed to stretch the spring so that is 0.75 meters long?

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A cyclist is moving with a speed of $6 ms^{-1} $, As he approaches a circular turn on the road of radius $120 \;m$ he applies brakes and reduces his speed at a constant rate of $ 0.4 \;ms^{-2} $. The magnitude of the net acceleration of the cyclist on the circular turn is

asked Aug 25, 2014 by meena.p

1 answer

A car of mass $750\;kg$ moves around a circular track of radius $50\;m$ with a speed of $10\;ms^{-1}$. What's the centripetal force on the car?

asked Aug 25, 2014 by meena.p

1 answer

A merry-go-round is turning at the rate of $10.0$ revolutions per minute. A $50.0\;kg$ youth is located $5.00 \;m$ from the axis of rotation . What is the centripetal force acting on him ?

asked Aug 25, 2014 by meena.p

1 answer

Which of the following is true, if no work is done by a force on an object?

asked Aug 25, 2014 by balaji.thirumalai

1 answer

Consider the four wheeled vehicle travelling round a track banked at an angle $\theta$ to the horizontal, as shown. Let the conditions be such that when the vehicle is moving with a speed of $v$ there is no sideways force. The forces acting are then weight acting at the centre of gravity $G$ of the vehicle, and the normal reaction $R_1$ and $R_2$ at the wheels. Which of the following values of $\theta$ satisfies the condition for no sideways force?

asked Aug 25, 2014 by meena.p

1 answer

A small car with a mass of $0.8\; kg$ travels at constant speed on the inside of a track that is a vertical circle with a radius of $5.0\ m$. If the normal force exerted by the track on the car when it is at the top of the track is $6.0\; N$, What is the speed of the car?

asked Aug 25, 2014 by meena.p

1 answer

A small car with a mass of $0.8\; kg$ travels at constant speed on the inside of a track that is a vertical circle with a radius of $5.0\; m.$ If the normal force exerted by the track on the car when it is at the top of the track is $6.0\; N$, what is the normal force on the car when it is at the bottom of the track?

asked Aug 25, 2014 by meena.p

1 answer

A cyclist has to lean inwards when negotiating a curved unbanked road. The cyclist leans with an angle $\theta$ to the vertical. $N$ is the normal reaction given by $N=mg$, where $m$ is the mass of the cyclist and the bicycle combined. The radius of the curved road is $R$. The force of friction is given by $F=\mu N$ where $\mu$ is the co-efficient of friction. Assuming the cyclist skids which of the following is true?

asked Aug 25, 2014 by balaji.thirumalai

1 answer

A feather is dropped on the moon from a height of $1.40\; meters$. The acceleration of gravity on the moon is $1.67 m/s^2$. Determine the time for the feather to fall to the surface of the moon

asked Aug 20, 2014 by meena.p

1 answer

Dhoni throws his bat vertically upwards with an initial velocity of $26.2\;m/s$ Determine the height to which the bat will rise above its initial height.

asked Aug 20, 2014 by meena.p

2 answers

Three blocks of masses $m_1, m_2$ and $m_3$, with $m_1 \lt m_2 \lt m_3$, are placed in contact with each other on a frictionless, horizontal surface, as shown. A constant horizontal force $F$ is applied to $m_1$ as shown. If the three masses are in the ratio of $1:2:3$, what is the ratio of the contact forces of the two heavier blocks, i.e, $F_2:F_3$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Three blocks of masses $m_1, m_2$ and $m_3$, with $m_1 \lt m_2 \lt m_3$, are placed in contact with each other on a frictionless, horizontal surface, as shown. A constant horizontal force $F$ is applied to $m_1$ as shown. What is the contact force on $m_3$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Three blocks of masses $m_1, m_2$ and $m_3$, with $m_1 \lt m_2 \lt m_3$, are placed in contact with each other on a frictionless, horizontal surface, as shown. A constant horizontal force $F$ is applied to $m_1$ as shown. What is the contact force on $m_2$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Two blocks of masses $m_1$ and $m_2$, with $m_1 \lt m_2$, are placed in contact with each other on a frictionless, horizontal surface, as shown. A constant horizontal force $F$ is applied to $m_1$ as shown. What is the contact force on $m_2$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

A large man and a small boy stand facing each other on frictionless ice. They put their hands together and push against each other so that they move apart. Which of the following is true?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Consider the following Atwood machine with three masses in the ratio m$_1$: m$_2$: m$_3$:: 1:2:3, hung with a massless string over a friction-less pulley. What is the tension in the string between masses m$_1$ and m$_2$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Consider the following Atwood machine with three masses in the ratio m$_1$: m$_2$: m$_3$:: 1:2:3, hung with a massless string over a friction-less pulley. What is the tension in the string between masses m$_2$ and m$_3$?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Consider the following Atwood machine with three masses in the ratio m$_1$: m$_2$: m$_3$:: 1:2:3, hung with a massless string over a friction-less pulley. What is the common acceleration of the system?

asked Aug 20, 2014 by balaji.thirumalai

1 answer

Two blocks (m$_1$) and (m$_1$), where m$_1 \gt\;$ m$_2$ are connected as shown on frictionless surface. Find the common acceleration of the masses, ignoring any friction effects.

asked Aug 20, 2014 by balaji.thirumalai

1 answer