A horizontal rope is tied to a 50 kg box on frictionless ice. What is the tension in the rope if: (b) The box moves at a steady 5.0 m/s?

Video transcript

Hi, everyone. In this particular practice problem, we are asked to determine the tension in the cable where we'll have a horizontal cable pulling a 55 kg refrigerator across a smooth service. And the fridge velocity is going to be constant and equal to plus two m per second. We're being asked, the tension of the cable and the four options are 0 27.510 and 540 newton of the tension force. So we will model the bridge as a point like particle and the fridge is moving along the X direction and velocity of the fridge is going to be constant because the velocity is going to be constant. And we know that acceleration, it's just essentially the rate of change of the philosophy over time. So because velocity is constant, then acceleration is also going to be 0m/s squared. I will also draw a free body diagram of our system. Just imagine that the square right here is our fridge and we will have a normal force right here. We will also have the actual weight of the fridge itself, which is M times G just like so and imagine that we have this as our frictionless or smooth service and we will have our tension in our cable pulling the fridge itself, which is the, which is the one that we want to find. So we want to apply Newton's second law along the X direction. And doing that, we will get Newton's second law F net in the X direction is going to equals to M multiplied by A X. And we found that A X equals to zero earlier because the velocity is constant. So F net X equals to zero and the only force acting upon the X direction is just attention. So tension will equals to zero. Newton. Thus the tension on the cable is going to be zero. Newton which will correspond to option A. So option A is going to be the answer to our particular problem and that will be all for this particular video. If you can still have any sort of confusion, please make sure to check out our, our lesson videos on similar topics and that'll be it. Thank you.