Recent questions tagged class11

A man is standing stationary with respect to a horizontal conveyor belt that is accelerating with $1 m/s^2$. What is the net force on the man if the coefficient of static friction between man's shoes and belt is 0.2, upto what acceleration of belt can the man continue to be stationary relative to the belt? Mass of man$=65 kg; g=9.8 m/s^2$

asked Jul 8, 2013 by meena.p

1 answer

All surfaces are smooth in the figure. Find F such that block of mass m resting on a wedge of mass M remains stationary with respect to wedge

asked Jul 8, 2013 by meena.p

1 answer

A ball of mass 1 kg is at rest in position P by means of two light strings OP and RP. The string RP is now cut and the ball swing to position Q. If $\theta=45 ^{\circ}$ . Find the tension in the string OQ when RP is cut $(g=10 m/s^2)$

asked Jul 8, 2013 by meena.p

1 answer

If $z_1\:\:and\:\:z_2$ are two complex numbers such that $|z_1+z_2|=|z_1|+|z_2|$, then $argz_1-argz_2=?$

asked Jul 8, 2013 by rvidyagovindarajan_1

1 answer

A body A of mass 1kg is resting on a table and connected to body B and C as shown. The surface are smooth and string and spring are massless. The string is inextensible. Find the extension in the spring if force constant of spring $=k=50 N/m$ take $(g=10 m/s^2)$

asked Jul 8, 2013 by meena.p

1 answer

A fireman has to carry an injured person of mass 40 kg from the top of a building with the help of the rope which can with stand a load of 100 kg. The acceleration of the fireman if his mass is 80 kg will be

asked Jul 8, 2013 by meena.p

1 answer

A disk of mass 10 gm is kept horizontaly in air by firing bullets of mass 5 g each. each at the rate of 10/s. If the bullet rebounds with which the bullets are fired is

asked Jul 8, 2013 by meena.p

1 answer

An inclined plane is inclined at an angle $\theta$ when the block placed on it is just at the point of moving down the plane. What can be the minimum acceleration with which the block can be moved up the inclined plane.

asked Jul 8, 2013 by meena.p

1 answer

The system as shown is released from rest. Neglecting friction and masses of pulleys, spring & rope the spring gets elongated if

asked Jul 8, 2013 by meena.p

1 answer

A horizontal force F is applied on a rod inserted between two identical blocks A and B placed over a rough surface as shown.Force F is gradually increased then which of the block will move first.

asked Jul 8, 2013 by meena.p

1 answer

If $z$ is a complex number where $1+z+z^2=0$, then the value of $(z+\large\frac{1}{z}$$)^2+(z^2+\large\frac{1}{z^2}$$)^2+(z^3+\large\frac{1}{z^3}$$)^2+.......................(z^6+\large\frac{1}{z^6}$$)^2$ = ?

asked Jul 5, 2013 by rvidyagovindarajan_1

1 answer

The complex number $z$ is such that $|z|=1,\:z\neq1\:and\:w=\large|\frac{z-1}{z+1}|.$ Then the real part of $w$ is ?

asked Jul 5, 2013 by rvidyagovindarajan_1

1 answer

An inclined plane makes an angle $30 ^{\circ}$ with horizontal. A groove $OA=5 m$ cut on the plane makes an angle $30 ^{\circ}$ with $OX$. A short smooth cylinder is free to slide down the groove under the influence of gravity. The time taken by the cylinder to reach from A to O is $(g=10 m/s^2)$

asked Jul 5, 2013 by meena.p

1 answer

A body of mass 50 kg is pulled by a rope of length 8 m on a surface by a force of 108 N applied at the other end. The force that is acting on the 50 kg mass, if the linear density of rope is 0.5 kg/m will be

asked Jul 5, 2013 by meena.p

1 answer

A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m. If a force P is applied at the free end of the rope, the force exerted by the rope on the block will be

asked Jul 5, 2013 by meena.p

1 answer

A boy standing on a weighing machine observe his weight to be $200 N$. when he suddenly jumps upwards, his friend notice that the reading increased to $400 N$. The acceleration with which the boy jumped will be

asked Jul 5, 2013 by meena.p

1 answer

A lift is moving downward with an acceleration equal to acceleration due to gravity. A body of mass M kept on the floor of the lift is pulled horizontally. If the coefficient of friction is $\mu$, then the frictional resistance offered by the body is

asked Jul 5, 2013 by meena.p

1 answer

An object initially at rest explodes into three fragments. A,B and C The momentum of A is P$ \overrightarrow i $ that of B is $\sqrt 3$ P $\overrightarrow j$ where P is positive number. The momentum of C into be

asked Jul 5, 2013 by meena.p

1 answer

A $250 \;kg$ boat $4.5\;m$ long is floating with out motion on still water, with a boy of mass $50\; kg$ at one end. If he runs to the other end of the boat and stops, by how much distance the boat moves back?

asked Jul 5, 2013 by meena.p

1 answer

A ball of mass m strikes an identical ball at rest with speed of 10 m/s. After collision which is assumed perfectly elastic the first ball is found to move with speed 8 m/s. Speed of $2 ^{nd}$ ball and angle between the paths of two balls after collision is

asked Jul 5, 2013 by meena.p

1 answer

A shell of mass 'M' moving with velocity 'V' suddenly explodes into two fragments. One of the mass 'm' is reduced to rest. Find the velocity of the other fragment.

asked Jul 5, 2013 by meena.p

1 answer

A rocket burns fuel at the rate of $200 kg/s$. The exhaust gases are ejected down with a velocity of $400 m/s$. The upthrust developed by the rocket engine is

asked Jul 5, 2013 by meena.p

1 answer

A car of mass $2 \times 10 ^3 kg$ is to travel over a turn of radius $0.75 km$ and slope of angle $5^{\circ}$ If coefficient of friction between wheel and road is 0.5 maximum speed the car can travel with out slipping is $(\tan 5^{\circ}=0.087)$

asked Jul 5, 2013 by meena.p

1 answer

A body of mass $4 kg$ is at rest on a horizontal table. The coefficient of friction between body and table is 0.3 . Find the acceleration of the body if a horizontal force applied on the body is 20 N

asked Jul 4, 2013 by meena.p

1 answer

Two masses of $10\; kg$ and $20\; kg$ respectively are connected by a massless spring. A pull of $100 N$ acts on the mass $20 kg$. If the instantaneous acceleration of 10 kg mass is $2 m/s^2$, what is the acceleration of $20 kg$ mass

asked Jul 4, 2013 by meena.p

1 answer

A man pushes a truck initially at rest and weighting $2.5$ tonne along a horizontal rail with a steady force of $200 N$. The resistance to the motion amounts to $30 N$ per tonne. The velocity of the truck at the end of 30 seconds is

asked Jul 4, 2013 by meena.p

1 answer

A man fires the bullet of mass m each with a velocity v from a machine gun. If he fires n bullets every second, the reactional force per second on the man will be

asked Jul 4, 2013 by meena.p

1 answer

Find the value of $ \sum_{n=1}^{200}i^n$

asked Jul 4, 2013 by rvidyagovindarajan_1

1 answer

The area of the triangle with vertices $z,iz\:\:and\:\:-iz$ is ?

asked Jul 4, 2013 by rvidyagovindarajan_1

1 answer

The complex number $z$, satisfying the equation $|\large\frac{z-5i}{z+5i}|=$$1$ lies on?

asked Jul 4, 2013 by rvidyagovindarajan_1

1 answer

A force of $(6 \hat i+8 \hat j) N $ acted on a body of mass 10 kg.The displacement after 10 sec. if it starts from rest will be

asked Jul 4, 2013 by meena.p

1 answer

If the normal to force is doubled, the coefficient of friction is

asked Jul 4, 2013 by meena.p

1 answer

Two bodies of masses m$_1$ (4 kg) and m$_2$ (3 kg) are suspended at the ends of a string of negligible mass passing over a friction-less pulley as shown here.The acceleration of the system is

asked Jul 4, 2013 by meena.p

1 answer

The linear momentum p of a moving body varies with time according to equation $p=a+bt^2$ where a,b are constants. Net force acting on the body is

asked Jul 4, 2013 by meena.p

1 answer

A man of weight 1 mg is moving up in a rocket with an acceleration 4g. The apparent weight of the man in the rocket is

asked Jul 4, 2013 by meena.p

1 answer

If the tension in the cable of $1000 \;kg$ elevator is $1000\;kg$ weight, the elevator

asked Jul 4, 2013 by meena.p

1 answer

A car is moving with uniform velocity on a rough horizontal road.Then according to Newton's first law of motion

asked Jul 4, 2013 by meena.p

1 answer

An aircraf flies a $400 km/hr$ in still air. A wind of $200 \sqrt 2 km/hr$ is blowing from south. A pilot wishes to travel from A to a point B north east of A .Find the direction he must steer and time of journey if $AB=1000km$

asked Jul 4, 2013 by meena.p

1 answer

An open lift is moving upward with velocity $10 m/s$. It has an upward acceleration of $2 m/s^2$ . A ball is projected upward with velocity $20 m/s$ relative to ground. Find the time when ball meets the lift

asked Jul 3, 2013 by meena.p

1 answer

If initial velocity of projection is $10 m/s$ and angle of projection is $60 ^{\circ}$, find range R.

asked Jul 3, 2013 by meena.p

1 answer

A ball rolls off top of a stair way with horizontal velocity $u\; m/s$ If height of each step is h and width of each step is b the ball will hit the edge of $n^{th}$ step if $n$ is equal to

asked Jul 3, 2013 by meena.p

1 answer

The number of complex numbers $z$ such that $|z-1|=|z+1|=|z-i|$ is ?

asked Jul 3, 2013 by rvidyagovindarajan_1

1 answer

If $\omega(\neq1)$ is a cube root of unity and $(1+\omega)^7=A+B\omega$, then $(A,B)=?$

asked Jul 3, 2013 by rvidyagovindarajan_1

1 answer

If the conjugate of a complex number is $\large\frac{1}{i-1},$ then the complex number is?

asked Jul 3, 2013 by rvidyagovindarajan_1

1 answer

Distance between frog and an insect on a horizontal plane is 10m. Frog can jump with maximum speed of $\sqrt {10}m/s$ minimum number of jumps required by the frog to catch the insect is

asked Jul 3, 2013 by meena.p

1 answer

The path followed by a body projected along y axis is given by $y=\sqrt 3 x-\large\frac{1}{2}$$ x^2$. If $g=10 m/s^2$ Then initial velocity of projectile is

asked Jul 3, 2013 by meena.p

1 answer

A particle moves a distance x in time t according to equation $x=(t+5)^{-1}$ acceleration of particle is proportional to

asked Jul 3, 2013 by meena.p

1 answer

A bus is moving with a speed of $10 m/s$ on a straight road. A scooterist wishes to overtake the bus in $100 s$. If the bus is at a distance of $1 \;km$ from the scooterist with what speed should the scooterist chase the bus?

asked Jul 3, 2013 by meena.p

1 answer

A ball takes t seconds to fall from height $h_1$ and $2t$ seconds to falls from height $h_2$.Then $h_1/h_2$ is

asked Jul 3, 2013 by meena.p

1 answer

A particle starts from rest from top of a smooth inclined plane of a given base. The time of fall is least when inclination of the plane to horizontal is

asked Jul 3, 2013 by meena.p

1 answer

Ask Questions, Get Answers