A wooden board hangs from a spring scale which measures 100 N when there is no wind. The board is oriented parallel with the ground below. The board has area = 2 m2 and has negligible thickness. When the air above the board moves at 4.9 m/s and the air below the board is stationary, the spring scale now read as:
a. 65N
b. 69N
c. 73N
d. 77N
e. 81N

Which car has the most kinetic energy? a. a car of mass 1000 kg with a speed of 3 m/s b. a car of mass 2000 kg with speed 7 m/s c. a car of mass 1000 kg with speed 7 m/s d. a car of mass 2000 kg with speed 3 m/s

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?

Argon, neon, and xenon are examples of