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a crowbar of 2m is used to lift an object of 800 N . if the effort arm is 160 cm. calculate the effort applied. ans is 200N but i dont know the process.​

User Rebel
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Answer:

Step-by-step explanation:

friend, imagine a seesaw of length 2 meters. Now place a kid weighing 800N (almost 82 Kg) on one end of the seesaw. To lift that kid up, you have to put some weight on your side of the seesaw. Now you are told that the distance from the pivot to your end of seesaw is 160 cm.

This means that the seesaw is not perfectly balanced but more of it is on your side or the pivot is far from you.

now substract 160cm from 2m and you get the distance between the kid and the seesaw which is 40cm.

Now let me introduce you to "Moment", it is a number which helps us calculate the missing value in this problem.

Moment = Force x Distance from the pivot

The moment of the fat kid ;

800N x 40cm = 32000

To lift that kid you have to get the same moment as his. ie (32000)

Now you know your distance from the pivot which is 160cm.

Moment = Force x Distance from the pivot

so substitute Moment for 32000 and the distance for 160 cm and assign a variable to the force.

32000 = F x 160cm

32000/160 = F

200 = F

The force required is 200N.

You have found out the force you need or the weight you need to lift that kid.

User Aiysha
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