questions concerning measurements, experiments, and activities that demonstrate physics and are safe to do at home, require at most one tool or ingredient not readily available, and can be interpreted or analyzed on one sheet of paper with accessible math.

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108
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3answers
4k views

Why is the vibration in my wire acting so oddly?

I was soldering a very thin wire today, and when I had one end firmly soldered, I accidentally bumped the wire diagonally with my tweezers. What I'd expect to happen is that the wire oscillates for a ...
13
votes
2answers
2k views

What's the problem with my Young slits experiment?

My Young's slits experiment doesn’t work. I mean I tried to see wave effect of light but I didn’t see any thing expect particles! I’ve sent you a pic of my laser and a short video of the experiment. ...
1
vote
2answers
42 views

How does sawdust selectively absorb water?

This Wikipedia page states that sawdust, cellulose etc. can be used to absorb water from azeotropic ethanol to produce anhydrous ethanol. How does this work? Why would the sawdust not simply absorb ...
0
votes
1answer
17 views

Current thru two series resistors, 1 small, 1 large

I have a circuit that has series resistors for a switching regulator. Voltage is 6V. There's a "current sense resistor" of .05 ohms followed by another resistor of say 1K. There's 1A flowing. The ...
3
votes
0answers
29 views

A cheap experiment to verify that a monitors intensity response is not linear

For the past year or so i have had to answer different questions on how the intensity response of a monitor behaves, nearly every week. Many of you probably know that the monitor intensity response to ...
-3
votes
0answers
51 views

Why does the Microwave disturb the Internet Signal?

I have no back round in physics but was wondering how come every time the microwave is turned on, the internet slows down dramatically?
1
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0answers
23 views

Heat exchanging Questions

I hope I am able to ask this in the way I am thinking about it. Is there a point, or at what point does water become ineffective for heat exchange. The reason I am asking, (My real world ...
1
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2answers
27 views

Does a flame put off a windlike force

When I hold a flame above a flame the one on top flickers and waves as if its about to go out. What is the cause of this?
1
vote
1answer
34 views

Can vernier scale ratio be less than 1?

I came across a question (See Image) that states about two vernier scales The first vernier scale is the top-most figure in the image: It has 10 vernier scale division equal to 9 main scale division ...
1
vote
1answer
69 views

How to measure the mass and balance point of a human forearm?

I've been trying to find this out for about a month now. I'm usually met with humorous but not really helpful comments about chopping my own arm off. I'm preferably looking to do this on a budget ...
1
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2answers
61 views

Lamina Pendulum Experiment help

I've been tasked with researching ways to find the gravitational acceleration g and its uncertainty together with the moment of inertia and and the moment of inertia's uncertainty. I have figured out ...
10
votes
5answers
2k views

Milk or sugar first to maximize temperature of a hot cup of tea?

If there is a hot cup of tea and we were asked to add milk and sugar, which mixing order would make the hottest tea? I personally think that the order doesn't matter, since sugar wouldn't change the ...
0
votes
3answers
99 views

An experiment to show sound waves

My 6 year-old son asked me to explain the sound barrier. I think I'm ready to explain, but I wanted to know if I could add a little homemade experiment to show visually how soundwaves are generated. ...
0
votes
1answer
26 views

Why is this ice cloudy at the center and has a transparent layer?

This fell at my place during a hailstorm. I can not figure it out why it is like this.
0
votes
2answers
50 views

Sound pitch of glass with water

I have a glass (made from glass) at room temperature. I poured very hot tea in it and started stirring. No extra tea is poured in the glass. When hitting the glass with the spoon, I noticed the ...
-1
votes
1answer
40 views

Why does this circuit work and the other doesn't? [closed]

if we connect the set up like this the bulb glows but if we connect the [right wire] to the [earth of the left] then the bulb [doesn't glow]. Why does that happen?
1
vote
0answers
39 views

Direct comparison of energy measurements for kids

I am planning a few physics & science sessions in the woods with 14 year-olds. The theme for one of the sessions is Energy, and my aim is to show them how gravity, solar radiation, wind (air ...
2
votes
0answers
44 views

Printing zone plate with laser printer

I tried to print my own zone plates on transparent plastic with laser printer with this generator. I prepared a lot of plates with different settings - focus from 4 to 60 cm, 3 wave lengths, etc. Yet ...
5
votes
1answer
47 views

Ideas for extending Muon-Life-Time experiment?

Background: I'm teaching a lab experiment for measuring the Muon lifetime. The experiment is a big tube of scintillator attached to a PMT. The muon entering the scintillator generates a reading in the ...
2
votes
1answer
53 views

Which will dry faster? [closed]

Assume that you have a wet shirt that you have just washed. You squeeze of the surplus water that can be squeezed out. Method 1: 1)You iron the shirt for 5 minutes and then hang it out to dry out in ...
0
votes
2answers
22 views

Would a hybrid mixed medium balloon allow you to use less helium to lift equivalent weight?

Suppose you had two balloons, one inside the other (a inside b). Would filling balloon "a" with the 80% nitrogen/20% oxygen mix you find in the surrounding air at ground level, and then filling ...
0
votes
1answer
28 views

How to insulate static electricity

This is a follow up question to Extending the reach of a crocodile clip for Kelvin Water Dropper experiment. We have resolved the issue, but now we have the following cable (in the image) that ...
1
vote
0answers
33 views

How to predict a flight distance? [closed]

I conducted an experiment by varying the stretch length of a rubber band (angle is always constant) which resulted in different flight distance. My teacher told me to find an equation/law to explain ...
1
vote
0answers
14 views

portable battery packs for decorative lights

I a set of home decorative lights that is powered by a portable 2 x D cell batteries. Can I replace the current pack with a new pack that takes AA batteries
4
votes
2answers
163 views

Is a DIY neutrino detector feasible?

How long does a neutrino detector filled with distilled water need to be to pick up neutrinos from one direction at about the level of a distant star within our galaxy? Would an off the shelf ...
0
votes
2answers
62 views

Is the video “How to Reveal Subatomic Particles at Home”'s explanation of its experiment misleading?

https://www.youtube.com/watch?v=wN_DMMQEhfQ The video asserts that along the path of an electron or muon, a trail of condensation will appear. But from what I understand, if an electron or muon (both ...
1
vote
2answers
73 views

Coefficient of friction and practical experience of sliding

The classical model of friction has a coefficient of friction depend only on the materials, but not area, and the force proportional to the normal force and coefficient of friction. So a given object ...
0
votes
1answer
167 views

Why we cannot hear ourselves or speak in water

I've tried several times to shout when I'm inside the pool but have failed to make any sound. Nor am I able to hear anyone talking outside. Why does this happen? The frequency does not change and ...
0
votes
1answer
51 views

resistance of wires

i have an upcoming open investigation at my school on wire resistance, in preparation for it i want to find out if duct tape would effect the multimeter's readings. i need to connect wire to a ...
22
votes
11answers
3k views

Backyard experiments to falsify the Flat Earth theory [duplicate]

I recently became aware that the flat Earth theory still exists in the 21st century, and has colored the views of a friend of mine. Roughly speaking, the tenets are: The Earth is a flat disk, with ...
0
votes
1answer
72 views

Will throwing oil on snow help it melt faster (significantly)? [closed]

The main thing that melts snow is the sun. Indeed, without the sun, the air itself would eventually turn to snow. The problem is, the sun melts snow inefficiently. The sun emits radiation (a lot of ...
1
vote
0answers
47 views

Rain experiment failed. Why?

I tried to make rain with a bottle and a balloon but it failed. The bottle was small, only a couple inches wide and the threaded part that I had the balloon on was less than an inch. In particular it ...
4
votes
2answers
79 views

How to design a simple experiment about force and motion for young kid?

I am planning to demonstrate experimental validation F = m*a - but to a 4th stand. student. By now he understands velocity and acceleration well enough. I want to design this experiment using ...
1
vote
2answers
84 views

What will hapeen if we remove air from a pipe [closed]

At first i did not know if this relate to engineering or physics but i think it mostly relate for physics so i posted here. My question is what would happen if we have a pipe set vertically and have ...
5
votes
1answer
59 views

Will the speed of the wind produced by a fan increase continously to infinity with the propeller spin speed?

Imagine a scenario: On a stand, an $RC$ plane motor is mounted on a stand. The motor has a $8x4$ prop attached to it. In the theoretical model, if the spin of the motor can be increased infinitely ...
1
vote
0answers
30 views

Is it possible to make a capacitor of required specifications using aluminium foil? [closed]

I wanted to make a FM radio transmitter but I was not able to get a capacitor with the exact rating of certain micro farad and pF. But I live in a poor country and I can not find them in the local ...
1
vote
1answer
48 views

Creating airflow in a mini greenhouse [closed]

How do I create the best airflow for a mini victorian style greenhouse, that has a total volume of 80148.75 cm3? I leave the lid on top, which is a triangular prism in structure, open about 2.54 cm. I ...
5
votes
1answer
206 views

Why does a stream of water behave like this when aimed against a spoon or into a glass?

I noticed while doing everything except the dishes that water behaves quite strange. These two things might be two different phenomenon, but the water acts in a similar way in both cases. Spoon and ...
3
votes
3answers
163 views

Why didn't the glass break?

In the figure below, a needle has been placed in each end of a broomstick, the tips of the needles resting on the edges of filled wine glasses. The experimenter strikes the broomstick a swift and ...
1
vote
1answer
95 views

What makes bathroom soap bars to crack during winter season?

Is there some relation between winter season and cracking of bathroom soaps? I noticed that , cracking happens only during winter season.I also learned earlier from physics stack that, During winter ...
1
vote
0answers
32 views

Approximating Gallons of Gas Needed for Trip (read: physics grad. with too much free time)

My departure from college has left me with an itch for physics-y problems to solve, and my boredom and free time gave way to this approximation of the gallons of gas I use for the trip to my ...
0
votes
2answers
34 views

smallest possible length of copper wire, where I can measure capacitance via multimeter [closed]

I am a new highschool physics instructor and I want to show to my students the basic concept inside the capacitors. i plan on showing them via simple 2 copper wires side by side each other, supplied ...
2
votes
0answers
37 views

Phenomenon of talking apple

Recently I noticed something weird when took a metal bowl with a few apples out of the fridge and left them to get warm. After a while I heard a distinct sound in the form of sharp clicks approx. ...
2
votes
1answer
35 views

What mechanism explains the effect of a hot surface on hydrogel balls?

Adding little hydrogel balls to a hot surface has an interesting effect as seen in this video. Hydrogels (as the name suggests) contain a lot of water but rather than melt or burst, the little balls ...
1
vote
1answer
110 views

Measure ball's acceleration down inclined plane

If I am asked to devise an experiment to find an expression for the acceleration of a uniform sphere (ball bearing) rolling down an inclined plane, as a function of the angle of incline. Hence deduce ...
1
vote
2answers
161 views

About the real reason why paper doesn't fall in HALF-FILLED inverted cup [duplicate]

I just happen to see a show about air pressure host by Brian Cox. As the link:http://imgur.com/EsRadFi shows, he flipped a half-filled water cup upside down then the paper on cup doesn't drop: It ...
3
votes
2answers
138 views

Time taken to cook frozen peas

I'm cooking frozen peas in my kitchen. Experiment 1 - I take a quantity of frozen peas, put them into a (room temperature) saucepan, add a quantity (at least enough to cover the peas) of boiling water ...
0
votes
0answers
92 views

I have some questions about reproducing Young's double slit experiment

I want to reproduce Young's double slit experiment for a school project. For the slits I am thinking making cuts in aluminium foil or maybe do something with pencil leads like this instructable ...
4
votes
3answers
73 views

Raw data acquirable from amateur astrophotography

What raw data can I possibly acquire from an 8" Classical Dobsonian Telescope, and a DSLR? Could anything eye-opening to amateur astronomers be computed or calculated first-hand with such equipment? I'...
1
vote
1answer
97 views

Why are exploding HHO bubbles louder then pure HHO?

We tried my electrolyzer with a friend today, we filled a small bottle with HHO gas, and set it on fire. It was loud but not a big deal, like a firecracker. Then we added some soapy water and created ...