Work Energy and...

The force required to stretch a spring varies with the distance as shown in the figure. If the experiment is performed with the above spring of half the length, the line $$OA$$ will:-

When two springs A and B with force constant $$ K_A and K_B $$ are stretched by same force,the respective work done on them is:

If two balls each of mass 0.06 Kg moving in opposite directions with speed 4 m/sec collides and rebound with the same speed,then coefficient of restitution for the collision will be:-

A particle moves along the x- axis from x=0 to x=5 m under the influence of a force given by $$F=7-2x+3x^2$$.Work done in the process is 

A gun fires a shell of mass $$1.5 $$kg with velocity of $$150$$ m/s and recoils with a velocity of $$2.5$$ m/s. 

A spring of natural length $$L$$ compressed to length $$7\ L/8$$ exerts a force $$F_0$$. The work done by the spring in restoring itself to natural length is 

The $$P.E.$$ and $$K.E.$$ of a helicopter flying horizontally at a height $$400\ m$$ are in the ratio $$5:2$$. The velocity of the helicopter is:

At the instant t= 0 a force F=kt( k is a constant) acts on a small body of mass m resting on a smooth horizontal surface.The time,when body leaves the surface is:

Identify the wrong statement

A time dependent force F = 6t acts on a particle of mass 1 kg. If the particle starts from set, the work done by the force during the first 1 sec. will be :