thanks a ton ..everyone

A railroad car of mass M is at rest on frictionless rails when man of mass m starts moving on the car towards the engine.If the car recoils with a speed v backward on the rails, with what velocity is the man approaching the  engine?.

What method are we going to follow.shud i proceed with conservation of momentum or its a  collision problem.Pls ellaborate    .2 rates assured.

thank u abhi

earpit, yeh stategy to mujhe bhi pata hai.mujhe application chahiya.Agar bas itna hi karna hai to solution bhi karke de do.I will be grateful to u.

Mr.verma (50 kg) and mr.mathur(60 kg) are sitting on the two ends of 4m boat of mass 40 kg standing still in water.To duscuss the mechanics of the problem they come to the middle of the boat.Neglecting friction with water, how far does the boat move on the water dsuring the process

pls explain the stategy to deal center of mass problems.

This is hcv prbl no 43 please refer the diagram .There is a spring attached to the bottom end of an incline of inclination 37 degree.A small block of mass 2kg starts slipping down the incline from a point 4.8m away from the spring.The block compresses the spring by 20 cm,stops momentarily and then rebounds through a distance of 1m up the incline.Find a) the friction coefficeient between the block and the plane B)spring constant

I am preparing for entrances in 2009.I have so much time left only six months left and i have done till circular motion in physics, chem about 3-4 chapters and calcullus till differentiation .I am much worried how will i complete so much.In my house i have lot of problems i am not able to study for 12-13 hours constantly.Bt i hd nt left trying, neither have i left, nor will i leave .I am very dtermined and hopefulI am very sincere and hard wrking..But i have no support from anyone and situations are not allowing me to study..Please suggest me how shud i face this difficult time and maintain concentration,positive belief and study.I was earlier preparing for iit but now i have dropped it and preparing for AIEEE.Atleast i can complete 90% of the topic and settle well for 4 yrs and then plan for further future.I have joined an online coaching which is good but too slow.Can they complete the course?I feel like crying.please tell me am i doing right?What shud i think and what not?What shud be my stategy?

A block of mass m  moves on a horizontal circle against the wall of a cylindrical room of radius R.The floor of the room on which the block moves is smooth but the friction coefficient between the wall and the block is mu.The block is given an initial speed Vo.As a function of speed v write a) the normal force by the wall on the block

b)frictional force by the wall and

c)the tangentaial acceleration of the block

Please give the FBD for the following and expalinn why are the directions taken so.

If  f(x) defined by f(x)=   

                                        1,x=0

                                        -1,x=1

then f(x) is continous for all x except x=0,1.how???????????

Please tell me what shud be our stategy to solve when we see mod values

Here' s a question

if f(x)= then

f(x) is continous for all x in its doman but not differentioable at x=-1,+1

please explain with the help of graph

A hemispherical bowl of radius R is rotated about its axis of symmetry which is vertcal. A small block of mass is kept at a position where the radius makes an angle theta with the verticl.The block rotates with the bowl without any slipping.The friction coefficient between the block and the bowl surface is mu.Find the range of the angular speed for which the block will not slip.

                                  Please draw the free-body diagram.Is it that normal force is always along the direction of force.pLese explain.

Find the average velocity of a projectile between the instants it crosses half the maximum height. It is projected with speed u at an angle theta with the horizontal.

A helathy youngman standing at a distance of 7m from a 11.8m high building sees a kid sliping from the top floor.With what speed should he run to catch the kid at the arms height(1.8m)