Rishi's Physics Thread

[Rishi97]

oh that makes sense now. Thanks
You used the constant accleration formula but why did u sub in 20sin(30) as u?
Sorry for the bombardment of questions. I have a sac tomorrow

[rhinwarr]

Using trig:
sin 30° = opp/hyp
sin 30° = u/20
u = 20sin30°

[Rishi97]

Using trig:
sin 30° = opp/hyp
sin 30° = u/20
u = 20sin30°

ohhhhh....thanks for that

[Rishi97]

What is the definition of apparent weight?
I don't want to just say "how you feel.."

[rhinwarr]

Apparent weight is the weight felt by the object due to the normal reaction force acting on it.

[Rishi97]

Can anyone please provide definitions to the following physics terms:
- Stiffness
- Yield strength
- Elastic
- Plastic
- Composite material
- Load force
- Cross sectional area
- Bending

Much appreciated

[Rishi97]

What is "load force" in regards to materials and structures?

[Phenomenol]

Can anyone please provide definitions to the following physics terms:
- Stiffness
- Yield strength
- Elastic
- Plastic
- Composite material
- Load force
- Cross sectional area
- Bending

Much appreciated

http://www.mediafire.com/view/61j4tg7r6s99lmo/Physics_Cheat_Sheet_Unit_3_+_4_(1.1).docx

My cheat sheet should have all these definitions. And then some.

What is "load force" in regards to materials and structures?

Usually the force applied by an object/objects that you want to do work on.

[Rishi97]

Can someone please help me with a question from the heinemann textbook. Sorry, I can't upload a pic.
Q 3b from 4.1 questions on electronic circuits
Why do both voltmeters display the same voltage?
Thanks guys

[Rishi97]

True or False?
If a globe has a higher resistance, will it have a greater potential difference?
Pls explain why
Thanks

[RKTR]

It will because V=IR  R increases , V also increases

[Rishi97]

In chapter 4.3 from the Heinemann textbook, in amplification, would the graph be linear?
It says, 'ideally' it should but sometimes there is a 'non-linear amplification'.
So, if a question asks if the resultant graph is linear or non-linear, what should I write?

Sorry for bombardment of questions

[Rishi97]

What is the definition for 'inverting amplifier'?

[rhinwarr]

In amplification, the 'linear' part of the graph refers to the sloped part where there is distortion-free amplification. That means the output voltage does not exceed the cut-off regions so there is no clipping. Non-linear amplification is the cut-off and saturation regions where output voltage does not change while input voltage changes. This causes clipping. So the resultant graph will depend on the question whether the input peaks voltages remain within the linear amplification output voltage range.

An inverting amplifier has a negative gain so inverts (changes the sign) of the input voltage.

[Rishi97]

A portable electric heater has the two settings, 'high' and 'low'. These heating levels are obtained by connecting two heating elements either in series or in parallel, across the 240-VRMS mains supply. Each element has the same electrical resistance. When the heating elements are connected in series, the total power dissipated in them is 960W.

a) WHat is the resistance of each element?
I used the formula P=V²/ R and found the R value to be 60 ohms. But since there are 2 elements, would I divide the 60 or multiply it?

Thanks