Can anyone help me with these problems? they are really stressing me out, thanx(adsbygoogle = window.adsbygoogle || []).push({});

1) The arm of a crane is 20.0 m long and makes an angle of 25.0° with the horizontal. Assume that the maximum load for the crane is limited by the amount of torque the load produces around the base of the arm.

What is the maximum torque the crane can withstand if the maximum load is 445 N?

I know that torque=fr sintheta, but this isn't as straight forward as it looks.

2.) A mechanic jacks up a car to an angle of 8.0° to change the front tires. The car is 3.20 m long and has a mass of 1160 kg. Its center of mass is located 1.12 m from the front end. The rear wheels are 0.40 m from the back end. Calculate the torque exerted by the car around the back wheels.

I know that to find the lever arm it's going to be cos8 2.4=-0.349. So then to find the torque it would be (870 kg)(9.8)(-0.349)=T The force would be the mass times 9.8 correct?

3.)A window washer is standing on a scaffold supported by a vertical rope at each end. The scaffold weighs 208 N and is 2.80 m long. What is the force each rope exerts on the scaffold when the 675 N worker stands 1.00 m from one end of the scaffold? (smaller force and larger force)

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# Homework Help: Torque problems are killing me!

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