Physics 198 Lecture 12: Lecture 12

What is the symbol of an ion with 16 protons, 16 neutrons, and 18 electrons?

A person is designing a 10X telescope. If the telescope islimitedto a length of 20 cm, what is
the approximate focal length of the objective?
A) 16 cm
B) 17 cm
C) 18 cm
D) 19 cm

The emf of a battery is E = 18 V. When the
battery delivers a current of 0.3 A to a load,
the potential difference between the terminals
of the battery is 16 V volts.
Find the internal resistance of the battery.
Answer in units of ohm's
.