Physics 2 Lab

Inside a Faraday cage the electric field

is zero

The charges generated by the VDG are because of

Frictional forces

Which of the following materials can be used to construct a Faraday cage?

None of these (semiconductor, non-conductor, insulator)

Which of the following statements is correct? 

A photon has no charge

An inductive charging (i.e. the reason why we used the smaller dome in the lab) acquires the opposite charge than the main Van de Graaf (VDG) dome is because

The repelling forces between electrons

The typical radius of an atom is closer to

10^-15m

An electrostatic luminous spark is a result of which of the following?

Collisions between ions or electrons and air molecules

One argues that because the proton is much larger in mass than the electron, it creates a much stronger electric field at the same distance than the electron does. This statement is 

False

The size of the VDG dome determines

All of these on the list (the electric potential magnitude on the surface of the sphere, how long the sparks can reach, how much charge is stored) 

Which of the following choices best represents the likely “byproducts” when accelerated electrons collide with air molecules? 

A photon

At its natural state, air is

an electrical insulator

At any given time, there are electrons in the air that we breathe. This statement is:

True

The charges on the VDG reside

on the surface

Which of the following quantities does the breakdown voltage of a gas depend on?

All of these (partial pressure, density, temperature)

The electric field at the center of the VDG dome is

Zero

The sound from the electrostatic luminous spark we observed in the lab is a result of

None of these on the list (the electron reduction from excited atoms, the photons produced from excited atoms, the electron production from exicted atoms)

A student argues that the light that is produced during the VDG spark is due to the thermal expansion of the surrounding air. This statement is

False

The neutron is much less massive than the proton. This statement is

False

Inductive charging is due to which of the following?

The Coulomb force

Where do charges reside on a randomly shaped conductor?

They always reside at the surface

The electron is less massive than the proton. This statement is:

True

The resistance of the semiconductor we studied in the lab:

exhibited non-Ohmic behavior

Ohm’s law is always obeyed across all electronic devices (e.g. bulbs, resistors, semiconductors, etc.). This statements is:

False

Momentum exchange between electron collisions is one of the parameters that determines the resistivity of a wire. This statement is:

True

Ohm’s law in AC and DC domain treats an equivalent resistor (i.e. combining more than one resistors into one) the exact same way. This statement is:

True

Ohm’s law in AC and DC domain treats an equivalent resistance (i.e. combining more than one resistors into one) the exact same way. This statement is:

True

The basic function of an oscilloscope is to return the electric potential difference across ANY element in a circuit with respect to which of the following?

Ground

Two different resistors in series connected to an AC supply will ALWAYS exhibit:

no voltage phase difference

The basic function of an oscilloscope is to return the electric potential difference across ANY element in a circuit with respect to which of the following? 

Ground

Two resistors R1 and R2 are connected in a parallel AC circuit but R1 gets hotter faster than R2. Which of the following conclusions can be safely assumed? 

R2 > R1

Is the statement “Ohm’s law is ALWAYS obeyed across all electronic devices” true or false?

False

Three 10-Ohm resistors that are made from the same material are connected in series. Which of the following quantities will ALWAYS be the same for the three resistors?

Current, voltage, and resistivity 

Momentum exchange between electrons is one of the parameters that determines the resistivity of a wire. This statement is:

True

Both Kirchhoff rules are NOT valid for AC current. This statement is:

False

The relative mean square (rms) quantity for electric potential in AC is ALWAYS:

greater than the numerical average of AC electric potential

In the lab we experimented on resistors in series in the AC domain. When we increased the frequency without changing anything else, we observed that the current of the circuit:

remained the same

Two resistors in parallel are made of the same material and have the same length and cross-section. Which of the following quantities will always be the same for these two resistors? 

All of these on the list (current, resistance, voltage, resistivity)  

Three 10-Ohm resistors that are made from the same material are connected in series. Which of the following quantities are the same for these three resistors?

All of these on the list (voltage, resistivity, current)

The phase difference between the AC voltages of two resistors in series dependent on which of the following?

This is no phase difference

Is the relative mean square(rms) quantity for electric potential in AC ALWAYS greater than or less that the numerical value of the AC electric potential?

Greater than

In an AC (sine-wave) domain, the time-series of the voltages between the capacitor and the entire circuit will ALWAYS be:

None of these (exactly 90, exactly 180 out of phase, exactly in phase)

In an AC (sine-wave) domain, the time series of the voltages between the capacitor and the resistor will ALWAYS be:

exactly 90

One of the major difference between DC and AC (sine-wave) that when the circuit includes a capacitor is that:

the capacitor has resistance, but dependent on frequency

In your lab experiment, you deduced that the speed of a capacitor discharging in a DC circuit is dependent on which of the following quantities?

Both on capacitance and resistance

Which of the following will cause the capacitance to increase?

None of these (increase the plate separation, increase the voltage across the capacitor, decrease the charge on the plates)

In your lab experiment, you deduced that as the AC source frequency increases in an RC in parallel, then the rms voltage across the entire circuit:

remains the same

In your lab experiment, you considered a capacitor and resistor in series in AC (sine-wave) domain. Did the time-series of the voltage across the capacitor ever become zero? 

Yes

The plates of an isolated parallel plate capacitor with a capacitance C carry a charge Q. What is the capacitance of the capacitor if the charge is increased to 2Q?

C

In your DC experiment, when the capacitor was just beginning to charge the current in the circuit was:

maximum

In your lab experiment, you observed that the discharging capacitor would exhibit:

the opposite polarity than it was charged at

Which of the following quantities is the capacitance dependent on?

Geometry and dielectric only

One of the major differences between DC and AC is that when the circuit includes a capacitor and a resistor in series, then:

the capacitance reactance depends on frequency

In you lab experiment, you deduced that as the AC source frequency