2. Your friend says that when he measured how much electricity was
provided by a battery, it was less than the potential energy in the battery.
He concluded that the transformation violated the Law of Conservation of
Energy. Do you agree? Explain, using the ideas of the Conservation of
Energy (answer in 3-4 sentences or a solid paragraph, or more).

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

The experiment done in lab is repeated, using a ball that has unknown mass m. you plot your data in the form of f 2 versus m/l, with f in rev/s, m in kg, and l in m. your data falls close to a straight line that has slope 3.19 m/(kg · s2). use g = 9.80 m/s2 and calculate the mass m of the ball.

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?