What is the mechanical advantage of the simple machine pictured? A. 8.3
B. 14.7
C. 1.9
D. 20.4

Which example has gravitational potential energy? a. a horse slowing down from a run b. an apple about to fall from a tree branch c. a bicycle being pedaled down a horizontal path d. beaker sitting on the floor

You can watch static electricity in action by rubbing an inflated balloon against your hair. your hair will actually stand on its end! it does this because each hair becomes charged, and they all repel one another.

Currents in dc transmission lines can be 100 a or higher. some people are concerned that the electromagnetic fields from such lines near their homes could pose health dangers. for a line that has current 150 a and a height of 8.0 m above the ground, what magnetic field does the line produce at ground level? express your answer in teslas and as a percentage of the earth’s magnetic field, which is 0.50 g. is this value cause for worry?