Cannot find the formula for tension

[dhago07]

Figure 5-48 shows four penguins that are being playfully pulled along very slippery (frictionless) ice by a curator. The masses of three penguins and the tension in two of the cords are m1 = 12 kg, m3 = 16 kg, m4 = 23 kg, T2 = 112 N, and T4 = 212 N. Find the penguin mass m2 that is not given.
Image :- http://edugen.wiley.com/edugen/courses/crs1650/art/qb/qu/c05/fig05_46.gif

I really cannot find the formula for tension at all and also i don't understand the tension concept at all. So please can somebody help me please.

Thanks

 

[LowlyPion]

Tension is just Force.

Use F = m*a

 

[cookie76]

Hello everyone,

I'm having a doubt with my Physics homework. I need somebody's help!

To find the force exerted by the rope on a bucket of water that is raised from a well I have to find the normal force (m*A upward accelaration of the bucket) and that is the one or I should find the force of gravity (m*G) and substracted from the normal force and that is the force exerted by the rope?

Thankss