Now what's this???

All the wires shown in the figure (red color) have resistance 'R'. The only places where the wires are connected are the vertices of the large hexagon.

Find the resistance between points
1)'A' and 'B'.
2)'A' and 'C'.

Friction:

What is the maximum weight of the block B which can be supported in the manner shown? (The pulley is smooth).


Note that the rod is nailed to the disc in the "black" region. The rod is also massless.

The coeff. of friction at the contacts b/w disc and surfaces is .3.

A rectangular block of mass 1 kg is trapped below a wedge (mass=10 kg). The dimensions of this block are negligible compared to those specified in the diagram.

One plans to take the block out by applying a pulling force to the left.

Answer the following questions:

1)What minimum force must be applied to accomplish this?


2)If this bare minimum force is applied:

a)What is the initial acceleration?

b)If the same force is applied to the right (pushing), what is the maximum displacement of the block?

c)What is the accn. when the block starts to come out of the bottom of the wedge?

d)If one continues to apply the same force for a very long time, what is
the acceleration at t=inf.


Assume the coeff. of friction at all contacts= .5.

Count:

Suppose that a weapons inspector must inspect each of 5 different sites twice, visiting one site per day. The inspector is free to select the order in which to visit these sites, but he cannot visit the site 'X' on 2 consecutive days.

Find the total number of ways in which the inspector can schedule his visits.

Here is a fixed circular track with a ball in it. The ball is projected with a speed V0 from the bottom of the track. This speed is more than that required to complete a circle.

Let normal reaction on the ball at the top of the track = N1.
At the bottom Normal reaction = N2.

Find N1-N2. Assume mass of ball = m.

Tark:

Shown is an iron rod supported by two vertical threads.

Mass of rod=M.
Separation b/w threads=L
Angle made by rod with the horizontal=Q

The tensions in the two threads are T1 and T2. Find T1/T2.

Because I can't think of anything better:

A hollow cylinder (radius=.5m) rolls without slipping down an incline. The length of the incline is 1m and the friction force acting on the cylinder is 200N.

Find the rotational work done by the friction force on the cylinder during its motion on the plane.