Third Law of Motion

Q. A bullet of mass m is fired from a gun of mass M. The recoiling gun compress a spring of force constant k by a distance d. Then the velocity of the bullet is :-

Q. Moment of a force of magnitude 20N acting along position x direction at 3m, 0, 0 about the point 0, 2, 0 is?

Q.

What Is Non-Impulsive Force?

Q.

Consider a book lying on a table. The weight of the book and the normal force by the table on the book are equal in magnitude and opposite in direction. Is this an example of Newton's third law?

1. Definitely Yes

2. Never, ever

3. Maybe, Depends on other factors like Temperature

4. none of these

Q.

Magnitude of force F experienced by a certain object moving with speed v is given by F = Kv³, where K is a constant. The dimensions of K are

1. [ML^-3T]

2. [ML^-2T]

3. [M^-2LT]

4. [MLT^-2]

Q. A balloon has 2 g of air. A small hole is pierced into it. The air comes out with a velocity of 4 m/s. If the balloon shrinks conpletely in 2.5s, theaverage force acting on the balloon is?

Q.

A block is placed on the table. What is the angle between the action of the block on the table and reaction of the table on the block?

1. 90⁰

2. 180⁰

3. 0

4. 30⁰

Q. On account of melting of ice at the north pole the moment of inertia of spinning of earth - a)increases b)decreasas c)remains unchanged d)depends on the time

Q.

A vessel at rest explodes into three pieces. Two pieces having equal masses fly off perpendicular to one another with the same velocity 30 metre per second. The third piece has three times mass of each of other piece. The magnitude and direction of the velocity of the third piece will be

1. 

2. 

3. 

4. 

Q. 15.A uniform chain of length l and mass m lies on a smooth horizontal table with its length perpendicular to the edge of the table, and a small part overhanging. The chain stars sliding down form rest due to the weight of the hanging part. Find the acceleration and velocity of the chain when length of the hanging potion is x.

Q. What the mg and normal forses are pair of action reaction forces give me full explanation how and why ?

Q. The velocity of a particle of mass 1 kg is given by v = (t3 + t) m/s. The average force acting on the particle between t = 0 to t = 2s will be

Q. 2 examples each for newtons 3 laws

Q. A position dependent force F acting on a particle and its force-position curve is shown n the fige Wok4Pon the particle, when its displacement 0 to 5 m isIN)

Q. what is the mass of a person if its weight is 40kg on earth

Q. A bullet of mass 50 g is fired form a stationary rifel into a wooden block of mass 1.95 kg placed on a horizontal wooden surface . on stricking, the bullet is embedded into the block and both together cover a distance of 200 m in a stright path before comeing to rest . given the coefficient of friction between the block and the surface is 0.2 and mass of the rifel form which the bullet is triggered is 14 kg, find magnitude of the velocity of the recoil of the rifel. ( neglat the rasistance of air on the bullet )

Q. (c) A greater force is required to im part greater velocity to an object. explain

Q. How to derive expression for moment of inertia of a body?

Q.

In the movie gravity, astronauts Sandra Bullock & George Clooney are stranded in space and connected by a string. To come closer to each other they both start pulling the string from their ends. Assuming that if the astronauts are pulling the string with a force F then the tension in the string should be equal and in opposite direction and should pull the astronaut (According to Newton's 3rd law).

Then in that case the net force on each astronaut should be 0 and they shouldn't move according to 1st law. Why are the moving towards each other?

1. None of these

2. Obviously George Clooney will pull with a greater force and that's why they two will come closer.

3. The question is wrong. This can never happen. In movie they use jet packs to come closer.

4. They come closer because of gravitational attraction between them the string has nothing to do with this

Q.

A boy kicked a stone and got hurt. Which property of stone is responsible?

1. Reaction

2. Momentum

3. Velocity

4. Inertia

Q. Why is it easier to pull a lawn roller than to push it?

1. Pulling decreases normal reaction.
2. Pulling involves sliding friction.
3. Pulling involves dry friction.
4. Pulling increases the effective weight.

Q. 46.If a rocket is going to upward direction, then mainly two forces will act on it mainly gravitational force and frictional force, so which force is applied to the rocket so it can go up ?

Q. Three rods each of mass m and length L are joined to form an equilateral triangle as shown in figure. What is the moment of inertia about an axis passing through the centre of mass of the system and perpendicular to the plane ?

Q. Two solid balls of identical size, one of iron and another of wood are released simul†an eously from rest from the same height . If equal force of resis†an ce acts on them then which ball will reach the ground firs

Q. 49. A monkey moves upwards with acc. g/2 w.r.t. rope then find the acc. Of block if mass of monkey and block is same I., e., M

Q. two block of masses m1 and m2 are connected by a massless string. Mass m1 is pulled by a horizontal forceF=60N as shown in figure.Tension in the string connecting two masses is

Q. A machine gun fires n bullets per second with speed u and mass of each bullet is m.If bullets hit a wall and rebounds with same speed then force acting on the wall is:- (1) nmu (2) 2nmu (3) 4nmu (4) nmu/

Q. A ball of mass, m is released from the top of an inclined plane of inclination tetha as shown.it strike a rigid surface ar a distance 3l\4 from top elastically. Impulse imparted to ball by the rigid surface is

Q. 9.Three rods each of mass m and length l are joined to form an equilateral triangle . What is the moment of inertia about an axis passing through the centre of mass of the system and perpendicular to plane?

Q. Give the magnitude and direction of force on a drop of water falling with constant speed from sky.