Classical Mechanics Answers

A spring of mass m is pulled such that a given instant, velocity of both of its end is v in the opposite direction. Find the kinetic energy of the spring.

Ques no. 64 & 65 on the image
http://i66.tinypic.com/2efuys5.jpg

Ques no. 64 & 65 from
http://i66.tinypic.com/2efuys5.jpg

An object initially at rest breaks into two pieces as the result of an explosion. One piece has twice the kinetic energy of the other piece.
What is the ratio of the masses of the two pieces?

What is the centre of mass of a L shaped body

Momentum is closely related to which of the following? and why?
(1) impulse
(2) kinetic energy
(3) angular momentum
(4) velocity

A particle with total energy E in Potential energy region U(x).Motion of the particle is restricted to the region when
options are
(a) U(x)>E
(b) U(x)<E
(c) U(x)=0
(d) U(x) < or = E

A car of mass m has an engine which can deliver power P.The minimum time in which car can be accelerated from rest to a speed v is
(a) (mv^2)/2P
(b) Pmv^2
(c) 2Pmv^2
(d) (mv^2)P/2

A pump is used to pump a liquid of density D continuously through a pipe of cross section area A.If liquid is flowing with speed v,then power of pump is
(a) (DAv^2)/3
(b) (DAv^2)/2
(c) 2DAv^2
(d) (DAv^3)/2

The blades of a wind mill sweep out a circle of area A.If wind flows with velocity v perpendicular to blades of wind mill and its density is D,then the mechanical power received by wind mill is
(a) (DAv^3)/2
(b) DAv^3
(c) (DAv^2)/2
(d) 2DAv^2