A: transformers work with either ac or dc electricity. true/false
b: power companies use high voltages to reduce power loss over long transmission distances. true/false
c: a(n) uses electromagnetic induction to increase or decrease voltage.
d: materials that lose all electrical resistance at low temperatures are known as and are ideal for constructing powerful electromagnets.
e: an electric device that uses an electromagnet to open and close a switch is a(n)

The ballistic pendulum was invented in 1742 by english mathematician benjamin robins. it consists of an initially stationary pendulum that moves after being struck by a bullet, and it is used to measure the original velocity of the bullet. the known variables are the bullet's mass m, the pendulum's mass m, and the height to which the block and bullet swing, determined by the length of the pendulum l and final angle θ. two principles of physics are necessary to solve for the bullet's original velocity. what are these principles? conservation of momentum and newton's third law conservation of energy and conservation of angular momentum grade summary deductions 0% potential 100% conservation of momentum and newton's second law. newton's second law and conservation of angular momentum. conservation of energy and newton's third law conservation of momentum and conservation of angular momentum. conservation of momentum and conservation of energy conservation of energy and newton's second law.

Use the table to answer question 22 23 and 24.

What is the conversion factor between kg/m^3 and g/m^3. express your experimental values for the densities in kg/m^3.