- #1

- 135

- 1

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter physics kiddy
- Start date

- #1

- 135

- 1

- #2

- 2

- 0

T=2m1m2g

----------

(m1+m2)

----------

(m1+m2)

- #3

- 2

- 0

t2 would be greater if the mass in t2 is greater than the mass in t1

- #4

Doc Al

Mentor

- 45,093

- 1,398

Is the pulley massless and frictionless? That's the key.I have attached a pic with my question. I want to know if T_{1}>T_{2}or not.

Careful! That's not true. In general you'll have toAs much as I know, Tension in a string = Earth's Gravitational force.

- #5

- 135

- 1

T1 has a mass greater than T2.

- #6

Doc Al

Mentor

- 45,093

- 1,398

I don't know what you mean. T1 and T2 are tensions. Regardless of the size of the mass on the ends of the string segment, the tension on both sides of a massless and frictionless pulley will be the same.T1 has a mass greater than T2.

Since the mass on each side of the pulley is the same (2m on each side, added up), it turns out that

- #7

- 1,506

- 18

There is no resultant force on this system so it is either at rest or moving with constant velocity (speed) in one direction or the other.

The only string with a different tension is between the 2 masses m and m ...the tension in here will be mg

The tensions T1 and T2 will be 2mg

- #8

- 7

- 0

I personally think that T2 was meant for the second string connecting the masses on the right side of the pulley. Because usually the pulley doesn't have mass (for beginner class) and the tension is uniform in one continuous string (and this is assumed rather than stated). So... I worked out the problem w these assumptions below. Check it out. So the solution looks like T1>T2.

- #9

- 1,137

- 0

Agree completely with DocAl and will add that the tension in a string is the same everywher.... all the way along it.

Only if the string is also of negligible mass

And if the pulley has some mass, you can find its moment of inertia and apply the equations of torque:

[itex]T_1 R - T_2 R = I\alpha = \frac{Ia}{R}[/itex]

Here I is moment of inertia of pulley and R is its radius ...

And if pulley has no mass, I=0 ...

- #10

- 135

- 1

I apologize for confusing you all. I am sorry. I have cleared my doubts with the question. The question was that there's a pulley and two masses 2m and m are tied to the opposite ends of the pulley as shown in the figure. The tension between 2m and pulley is T_{1} and between m and pulley is T_{2}. Is the tension T_{1}>T_{2}?

The pulley and string are assumed to be massless and frictionless.

The pulley and string are assumed to be massless and frictionless.

Last edited:

- #11

Doc Al

Mentor

- 45,093

- 1,398

Are you sure that TThe tension between 2m and pulley is T_{1}and between m and pulley is T_{2}.

(Is this your diagram, or the one given with the problem?)

- #12

- 135

- 1

Yes, I am sure.

- #13

Doc Al

Mentor

- 45,093

- 1,398

In that case, your question has already been answered.Yes, I am sure.

- #14

- 135

- 1

I can't figure out where the answer is. Please explain it once again. Thanks

- #15

Doc Al

Mentor

- 45,093

- 1,398

See post #6.I can't figure out where the answer is. Please explain it once again. Thanks

Share: