A 37 kg father fashions a swing for his children out of a long rope that he fastens to the limb of a tall tree. As one of the children swings from this rope that is 7.3 m long, his tangential speed at the bottom of the swing is 4.0 m/s. Required:
a. What is the centripetal force of the child at the bottom of the swing?
b. What provides the centripetal force that keeps the child moving in an arc?

1. gravitational acceleration
2. the height of the tree
3. the tension in the rope
4. the weight of the child

the force on the thing and the distance the force moves the thing

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

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the only real purpose of sputnik 1 was to beat the us into space. we were getting close to launching a useful satellite, explorer 1 - which launched on january 31, 1958. the ussr had to beat that, so they launched sputnik 1 on october 4, 19