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I don't know how to do this physics question!!! please help!?

A crane cable that is capable of withstanding 22,000N is attached by hook to a 2000kg block that is resting on the groundThe cable initially starts lifting the block at the maximum acceleration that the cable can withstand for 2 secsit then continues to raise the block at constant velocity for 5 secsAt this time the block slips off the hook at the end of the cable.calculate: the tension in the cable when the block is moving at constant velocity (which I worked out to be 19,000N??)ii) the maximum acceleration the cable can withstand.iii) the maxheight the block reaches above the ground.also please explain becuz i don't just need the answers i need to know how to do these types of problems i have the worst teacher and really can't do these problems!! thanx!!


Hello Confusinglyinlove ii) The maximum acceleration? Now,he's already given you the maximum Force that the crane can stand, right? 22,000 N And we know that F m a So, we know two of the variables, we can solve for the third a F / m a (22.000 N) / (2,000 kg) a 11 m/s^2 iii) First you need to know the speed the block was moving when it changed from accelerating to constant velocity (at 2 sec)Now we know that Change in velocity equals acceleration times the time V a t So for the first two seconds, it accelerates at 11 m/s^2 V 11 m/s^2 / 2 secs 22 m/s Now how far did it travel in the first 2 seconds? There are several equations you can use hereThe change in distance equals one half the change in velocity multiplied by the timeDistance 1/2 (Vf - Vi) t Distance 1/2 (22 m/s - 0 m/s) 2 sec Distance (in first 2 seconds) 22 meters Now add the Distance in the last 5 seconds, the velocity multiplied by the time Distance (in last 5 seconds) 22 m/s 5 sec 110 meters The total distance is 22 m plus 110 m 132 m Good Luck

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