Determine the resistance and the power Consumpten of a resistor that must be placed in series with a 75 ohms resistor
Accross 120 volts Source in Order to limit the Power Consumption
h the 75 ohms resistor to 90 watts.​

The magnitude of the poynting vector of a planar electromagnetic wave has an average value of 0.939 w/m2 . the wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. how much total electromagnetic energy falls on the area during 1.0 minute

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

What was the first instrument to ever record an earthquake?