## Coffee Drop Experiment

Coffee drop experiment For the coffee filter the graph of position shows that it does not bounce out. Although we have done a fit with a quadratic equation, the coefficient… Click here to read more

Physics tutorials, questions and answers

This site was started back in 2008, and features, among others, a collection of physics homework exercises and tutorials for all levels of physics students (high school and college).

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Coffee drop experiment For the coffee filter the graph of position shows that it does not bounce out. Although we have done a fit with a quadratic equation, the coefficient… Click here to read more

Ball drop experiment Data was recorded for position and velocity as function of time. For position the floor is considered to be at a distance of 2 m. We have… Click here to read more

The definition of the effective charge In this paper we will determine the effective charge of an electron. The effective charge is by definition the ratio (e/m). Background Information and… Click here to read more

The charged sphere A spherical shell has spherical symmetry and because of this we write its potential as $V(R,theta)=V_0(theta)$ ($theta$ is the “polar” angle of the spherical coordinate system). a)… Click here to read more

The icy slope A frictionless icy slope of angle $\theta$ having a length $L$, followed by a horizontal portion, then by a bump ($R$) make a frictionless path as in… Click here to read more

Circle moment of inertia Find the principal moments of inertia of a circle of radius $R$ and mass $m$. Use the integration over the circle length. (Hint: first define the… Click here to read more

The Bridge In the figure is presented a Wien Bridge. When its two arms are at equilibrium ($R1*R3=R2*R4$) the voltage on the Wien bridge diagonal cancels. You apply to this… Click here to read more

The Analog-Digital Converter The input range of a 10 bit ADC varies from +0.1..+4.9V. a) What input step size has this analog-digital converter? b) For a full scale sine wave… Click here to read more

Pendulum Laboratory The equations of pendulum are $T= C * \sqrt{L/g}$ (1) $T= 2\pi * \sqrt{L/g} * [1+(1/2)^2*\sin^2(x/2)+(3/4)^2*\sin^4(x/2)]$ (2) 1. For which angle is the period given by pendulum equation… Click here to read more

The supernova expansion In a supernova explosion, initially the supernova expands freely. Then the supernova enters a new stage when in the existent gas around the star, shock waves push… Click here to read more

Pipe Acoustic Impedance Let us suppose that we want to send an acoustic wave from left towards right through a series of connected pipes having different areas. What is the… Click here to read more

The falling electron Using the classic EM framework, a falling electron $e^-$ (a negative charge) emits energy/time as $W= (2/3)*(a^2e^2/c^3)$ (erg/s) where $a$ is the acceleration of the falling electron… Click here to read more

MOVE and CLR 8. If the value stored in the data register of Motorola M68000 D0 = \$ABCD1234, what is the data found in register D0 at the end of… Click here to read more

Velocity as function of time You are given the dependence of velocity as function of time from the figure. Please find the position as function of time from the given… Click here to read more

Question 1 A classic radiotelecope detects a planet’s hydrogen emitted waves of $\lambda=21 cm$. If the signal emitted by a planet has a wavelength that is 0.28 cm longer than… Click here to read more

In general dividing by 2 is equivalent to right shifting with 1. Also left shifting with 1 is equivalent to multiplication with 2. (a) Is a right shift equivalent to… Click here to read more

EM wave propagation An EM wave goes through the athmosphere of Earth (considered inhomogeneous) having an index of refraction of $n(z)$. This index of refraction depends on altitude $z$ as:… Click here to read more

Hermitian definition Please find if $(\overrightarrow p*\overrightarrow r)\overrightarrow L$ is hermitian or not. Please state the definition of a hermitian matrix? Which are the matrixes or $\hat r$, $\hat p$… Click here to read more

The flight centrifuge A flight centrifuge was designed to simulate the flight in a space vehicle. The arm which is $d=40 ft$, rotates about axis A-A. The cockpit rotates itself… Click here to read more

Classical electron We know from theory that a charge (an electron) that is accelerating in an atom, gives out energy at a rate of $W=\frac{2}{3}\frac{a^{2}e^{2}}{c^{3}} (ergs/s)$ where $c$ is the… Click here to read more