a chain of mass 'm' length 'l' and its l/5 partis hanging below the table .how much work is needed to pull it.

Answer 1

The information that was not supplied is assumed:
1. Links of the chain are very small
2. The surface along which the chain is pulled is frictionless
3. The chain has a uniform linear density

The work done W is the

W= mg (integral of(h dh) from 0 to 1/5L)
or
W=0.5(pg)h^2
p– Chain linear density
g – Gravitational acceleration
h – The length of the chain that needs to be pulled up

p= m/L (mass of the chain (m) over its length (L))
h=L/5

then we have

W=.5(pg)(1/25)=pg/50=(mg)/(50 L)

Answer 2

the quick way: The area of the chain striking over the ingredient has mass of M/4. Its center of mass is at distance L/8 below the table. The artwork mandatory to advance the chain equals the flair potential it is going to benefit by being raised. W = mgh = (M/4)g(L/8) W = MgL / 32 The good distance: evaluate a small area of the chain with length dx, striking a distance x below the table. The chain has mass according to unit length of M/L. So the mass of this small piece is M/L * dx returned, artwork equals the ease in potential potential. dW = dm * g * x dW = M/L * dx * g * x combine this from x = 0 to x = L/4 to come across the artwork required to advance the completed a million/4 of the chain. ?dW = ?(Mg/L) x dx W = Mg/L a million/2 x^2 from x = 0 to x = L/4 W = Mg/L a million/2 (L/4)^2 W = MgL / 32

Answer 3

W = F.S

here
S=l

and for F

F=m.a

a=9.8m/s^2

so F=9.8m

As the gravity is pulling the chain down with this much amount.

So the work required to pull the chain up is

W=9.8 (ml)

Answer 4

You don;t need work to pull it, you need force. The work is how much energy you have used and this depends not only on the force but the disctance over which the force is applied. The force depends on how hard you pull it, the amount of friction, etc.

So I really cannot answer your question, no one can, sorry.

Answer 5

mass hangng= m/5

centre of mass lies at distance L/10 from the table.

Workdone = m/5 *g* l/10 === answer.