The image shows copper wire coiled around an iron nail and connected to a battery to create an electromagnet. which factors determine the strength of this electromagnet? a. the voltage of the battery and the size of the switch b. the size of the nail and the size of the switch. c. the amount of electric current and the number of wire coils around the nail d. the number of coils of wire around the nail and the length of the wire in the circuit

1. a camcorder has a power rating of 19 watts. if the output voltage from its battery is 7 volts, what current does it use?answer units 2. a 1.5m wire carries a 6 a current when a potential difference of 57 v is applied. what is the resistance of the wire? yourunits 3. a clothes dryer uses about 2 amps of current from a 240 volt line. how much power does it use? yourunits 4.

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.