Recent questions and answers in Work, Power and Energy

A ball is dropped from a height of h from ground. If the coefficient of restitution is e, the height to which the ball goes up after it rebounds for the nth time is

answered Mar 5, 2018 by yashuvats.42

2 answers

A cable that weighs 1.5 kg/meter and is attached to a bucket that weighs 75 kg. Initially, there are 500 kg of grain in the bucket and as the bucket is raised 2 kg of grain leaks out of a hole in the bucket for every meter the bucket is raised. The bucket is 200 meters below a bridge. How much work is required to raise the bucket to the top of the bridge?

answered Dec 21, 2015 by vijayalakshmi.r

1 answer

A spring whose natural length is 15 cm exerts a force of 45 N when stretched to a length of 20 cm.Find the work done in stretching the spring from a length of 20 cm to a length of 25 cm

answered Sep 2, 2014 by sreemathi.v

1 answer

A force of 1200 N compresses a spring from its natural length of 18 cm to a length of 16 cm. How much work is done in compressing it from 16 cm to 14 cm?

answered Sep 2, 2014 by sreemathi.v

1 answer

A spring is stretched 60 cm, and it takes a force of 40 Newtons to hold it there. How much work did it take to stretch the spring to this point?

answered Sep 2, 2014 by sreemathi.v

1 answer

A wall is tilted in by $15^{\large\circ}$,and a 2kg block is placed against the wall.The block is held in place with a spring.The coefficients of friction between the block and the wall are $\mu_s=0.61$ and $\mu_k=0.49$.Holding the block in place requires that the spring be compressed by 12cm.What is the spring constant of the spring?

answered Sep 2, 2014 by sreemathi.v

1 answer

It takes 100J of work to stretch a spring 0.5m from its equilibrium position.How much work is needed to stretch it an additional 0.75m?

answered Sep 2, 2014 by sreemathi.v

1 answer

A force of 6 N is required to stretch a string from a natural length of 4 m to a length of 4.5 m.What work is required to stretch it to a length of 6 m.

answered Sep 2, 2014 by sreemathi.v

1 answer

Suppose 2 J of work is needed to stretch a spring from its natural length of 30 cm to a length of 42 cm.Then how far beyond its natural length will a force of 30 N keep the spring stretched?

answered Sep 2, 2014 by sreemathi.v

1 answer

Suppose 2 J of work is needed to stretch a spring from its natural length of 30 cm to a length of 42 cm.Then how much work is needed to stretch it from 30 cm to 40 cm.

answered Sep 2, 2014 by sreemathi.v

1 answer

A spring has a length of 15.4 cm and is hanging vertically from a support point above it.A weight with a mass of 0.200 kg is attached to the spring,causing it to extend to a length of 28.6cm.What is the value of the spring constant?

answered Sep 1, 2014 by sreemathi.v

1 answer

A spring has a natural length of 18 inches and a force of 20 lbs is required to stretch and hold the spring to a length of 24 inches. What is the work required in ft-lbs to stretch the spring from a length of 21 inches to a length of 26 inches?

answered Sep 1, 2014 by sreemathi.v

1 answer

A spring has a natural length of 1 meter.A force of 25 Newtons stretches the spring by $\large\frac{1}{4}$ of a meter.Determine how much work is done by stretching the spring from a length of 1.5 meters to 2.5 meters.

answered Sep 1, 2014 by sreemathi.v

1 answer

A spring has natural length 30 cm,and a force of 50 Newtons(N) is required to extend it to 35 cm.How much work is required to extend it from 32 to 36 cm?

answered Sep 1, 2014 by sreemathi.v

1 answer

A spring has a natural length of 20 cm. A 40 N force is required to stretch (and hold the spring) to a length of 30 cm. How much work is done in stretching the spring from 35 cm to 38 cm?

answered Sep 1, 2014 by sreemathi.v

1 answer

A block whose mass $m$ is $15\; kg$ slides on a horizontal frictionless surface with a constant speed $v$ of $3.7m/s$.It is brought momentarily to rest as it compresses a spring in its path.By what distance $d$ is the spring compressed?The spring constant $k$ is $1500\;N/m$

answered Sep 1, 2014 by sreemathi.v

1 answer

A spring has a natural length of 14 meters.If a force of 5N is required to keep the spring stretched 2 meters.How much work is done in stretching the spring from its natural length to a length of 18 meters.

answered Sep 1, 2014 by sreemathi.v

1 answer

A gas in a piston cylinder assembly undergoes an expansion process where $PV^{1.5}$=constant.The initial pressure is 3 bar,the initial volume is $0.1m^3$ and the final volume is $0.2m^3$.Determine the work done for this process.

answered Sep 1, 2014 by sreemathi.v

1 answer

We have a cable that weighs 2lbs/ft attached to a bucket filled with coal that weighs 800lbs.The bucket is initially at the bottom of a 500 ft mine shaft.Determine the amount of work required to lift the bucket to the midpoint of the shaft.

answered Sep 1, 2014 by sreemathi.v

1 answer

A particle of mass 0.5 kg moves on the positive $x$-axis under the action of a variable force $\large\frac{40}{x^2}$ newtons,directed away from origin..The particle passes through a point 2 metres from origin,with velocity $8ms^{-1}$ away from origin. Its experiences a constant resistance force of 6 newtons. Find the speed of the particle when it is 5 metres from origin.

answered Sep 1, 2014 by sreemathi.v

1 answer

Find the work done by F as it moves from a to b.

answered Sep 1, 2014 by sreemathi.v

1 answer

A 106g bullet is fired from a rifle having a barrel 0.441m long.Assuming the origin is placed where the bullet begins to move,the force exerted on the bullet by the expanding gas is $F=a+bx-cx^2$,where $a=13500N,b=8170N/m,c=24000N/m^2$,with $x$ in meters.With what velocity does the bullet exit the barrel?

answered Sep 1, 2014 by sreemathi.v

1 answer

A 106g bullet is fired from a rifle having a barrel 0.271m long.Assuming the origin is placed where the bullet begins to move,the force exerted on the bullet by the expanding gas is F=a+bx-cx$^2$,where a=13500N, b=8170N/m,c=24000N/m$^2$,with x in meters.Determine the work done by the gas on the bullet as the bullet travels the length of the barrel.

answered Sep 1, 2014 by sreemathi.v

1 answer

Force $F=(3x^2N)i+(4N)j$ acts on a particle changing only the kinetic energy of the particle.How much work is done on the particle as it moves from coordinates (2m,3m) to (3m,0m)?

answered Sep 1, 2014 by sreemathi.v

1 answer

What work is done by a force $F=(2xN)i+(3N)j$,with $x$ in meters,that moves a particle from a position $r_i=(2m)i+(3m)j$ to a position $r_f=-(4m)i-(3m)j$?

answered Sep 1, 2014 by sreemathi.v

1 answer

A particle moves along the $x$-axis from $x=0$ to $x=1$ under the influence of the force $F=(1+x^2)^{-1}$.Find the work done by this force.

answered Sep 1, 2014 by sreemathi.v

1 answer

A force $F_x$ acts on a particle.The force is related to the position of the particle by the formula $F_x=Cx^3$,where $C$ is a constant.Find the work done by this force on the particle when the particle moves from $x=1.5\;m$ to $x=3\;m$.

answered Sep 1, 2014 by sreemathi.v

1 answer