Finding tension on multiple points.

[squalami]

1. A 1.0-m-long massive steel cable drags a 20 kg block across a horizontal, frictionless surface. A 100 N force applied to the cable causes the block to travel 4.0 m in 2.0 s.Graph the tension in the cable as a function of position along the cable, starting at the point where the cable is attached to the block.

2. F = T = ma

3. i was taught that if you have a frictionless surface that the tension in a rope will be the same throughout the rope but i keep getting a wrong answer. . .

 

[rl.bhat]

Hi squalami welcome to PF.
In the problem, the displacement and time is given. Find acceleration a of the block and the cable.
Find the force F required to move the block using m*a. This force is less than 100 N.
Find the difference (100 - F). That is force required to move the cable. From that find the mass of the cable. Then proceed like connected mass type problem.