NO ONE WILL HELP ME!!! IT'S MULTIPLE CHOICE!!! PLEASE HELP!!!
1.) A 2.0 x 2.0 -inch slide is placed before a converging lens 21 inch in front of the focal point. If the focal length is 20. inches, how large is the image that is projected on the screen? ______ inches
42 x 10.
40. x 40.
420 x 420
2.)Four beats per second are heard when an unknown tuning fork and a 240 Hz tuning fork are struck simultaneously. This same unknown tuning fork and a 250 Hz tuning fork are struck. Six beats are heard. Its exact frequency:
is 256 Hz
is 236 Hz
is 244 Hz
cannot be determined