The pogo stick has a spring with spring constant 2.0×104n/m. when the child makes a nice big bounce, he finds that at the bottom of the bounce he is accelerating upwards at 9.8 m/s2 . how much is the spring compressed?

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?