You NEED to Practice This in A Level Physics

My Physics Tutoring: zphysicslessons.net/physics-t...
Get confident in Practical Skills Questions: / @zhelyo_physics
My Physics Workbooks: zphysicslessons.net/my-workbooks
Here is a variation of a very typical motion and forces question in A Level Physics. It looks at the power output to go up/down an inclined slope and then to estimate one of the distances.
Variations of this question keep appearing in many exam boards including AQA A Level Physics, OCR Physics A and B, Edexcel A Level Physics, CIE etc. and similar courses such as AP Physics, IB Physics etc.
I hope this problem is useful!
Please note some of the values may not be accurate as I thought of them "on the spot" while doing the problem to illustrate the concept and that I am assuming that the car acts as a single material point and I am not considering the effect of torques and moments.

[@zhelyo_physics]

Multi Step Calculations VS Describe and Explain Questions....? : )

[@mediarblx_npc]

Such a crucial skill that he's becoming more redder than his own shirt

[@Thembs154]

Hahhhh u killed me right there man😅😅😅

[@zhelyo_physics]

I was just moving away quickly so the light was being redshifted : )

[@lolaharwood619]

Must've been going fast, i assume we have to ignore all relativistic effects again?

[@Thembs154]

@@lolaharwood619 what?

[@lolaharwood619]

@@Thembs154lights source has to be travelling away from you pretty quickly to redshift, if he was moving that fast then his apparent mass would seriously increase among other things. You've never seen the comment "ignore relativistic effects " in your physics papers?

[@theowhittaker5682]

I think you are also able to solve it without even using the power of the engine or the velocity, only using the fact that it is at constant speed therefore you know all forces are balanced according to Newtons 1st law. You can construct a right angle triangle force diagram with a hypotenuse mg ( 800 * 9.81 = 7848) and side length of f (1000). Then you can just use trig to work work out θ which comes out as 7.32°

[@zhelyo_physics]

excellent!

[@Xarishher]

I answered this question in a rather unconventional way, I did the usual "F=ma for the Car up the slope", got value of sin(theta) as 125/981. Then, by using sin(theta) is O/H, I worked out the Adjacent Side using Pythagoras. Then, with Opposite and Adjacent I got tan(theta). I used proportionality, with the angle between component of weight and the angle between the slope. 973 was the adjacent side - I divided this by 100 given in the question which was the adjacent of the slope and got a constant of proportionality (k = 9.73). Using this I did the same for "O" in sin(o/h) = sin(125/981), I got 125 = h * 9.73 h = 12.8m

[@zhelyo_physics]

excellent work!!

[@umermustafa2857]

It's ok zoro you might not take the conventional route but you always end up at the final destination before anyone else on the crew

[@Xarishher]

@@umermustafa2857 🤣🤣🤣

[@gelloexe5389]

nice quick and short videos

[@zhelyo_physics]

thank you! I try to keep my videos either short and up to the point or like 1 hour but also up to the point : )

[@Dan-pi6dx]

you should do a series on alevel maths mechanics

[@zhelyo_physics]

I have been thinking about ZMaths for a while: )

[@pratyasha279]

@@zhelyo_physics sir i agree that would be so good tho

[@spectrum4real208]

This is a v3ry good idea

[@ahmedxaziz2960]

Sir can you explain why each component acts in certain way, so it’s more clear on future videos, for example why does gravity acts same direction as force wundnt it be vertical down to the ground from center of mass?

[@zhelyo_physics]

sure! So we are just looking at a component of gravity, the component parallel to the slope. Fully explained in this separate video: kzbin.info/www/bejne/faLcemawoZ6DldEsi=MvDNowUq2uCy2u9t Hope this helps!

[@plop.mp3246]

Hi sir, Could you please explain multiple choice question 8 of OCR A AS level Physics paper 1 (Breadth in Physics) 2020? {its about mean drift velocity of charge carrier in a 300 ohm resistor}

[@zhelyo_physics]

So the current splits at the junction so I_total=V/200+V/300=5V/600 i.e. I=5V/600 which is the total current that goes in What is the proportion of the total current that the 300 Ohm resistor gets? I_300=V/300 I_300/I_total=(V/300)/(5V/600)=2/5=0.4 and if the currents ratio is 0.4 the mean drift velocity is also 0.4 due the I=nAev equation if everything else is constant.

[@ishaana486]

do you know when you are releasing your next olympiad prep videos?

[@zhelyo_physics]

thanks for asking! it would be either this weekend or early next week : )

[@ishaana486]

@@zhelyo_physics great to hear!

[@engineeringmadeasy]

Hi, I'm doing OCR A Level Physics, I'm going to start revise Module 5. Is there anything that I need to know from Module 4 for Module 5? Thanks

[@zhelyo_physics]

good question. For OCR A diffraction gratings are done in the astrophysics part of Module 5, which is essentially waves, so sometimes you can get combinations. You will also need to know the formulas for the energy of a photon, E=hf and E=hc/wavelength. I've covered all here: kzbin.info/www/bejne/aojWY3Rsndilf5Isi=dMnUUdqBEOxr6ap8 Hope this helps!

[@user-xo1dx1gv6z]

Hey ZPhysics can make a video for foundation for the math's and all the way through calculus based physics like knzhou advice

[@zhelyo_physics]

thanks for the idea!

[@user-xo1dx1gv6z]

@@zhelyo_physics Thanks for reading my comment. I'm actually in 7th grade and I'm honing my foundations Algebra I, II up to Calculus and I'm still on unit 3 of Khan Academy's Dimensional Analysis and is there somehow any advice you can give to me? I've been doing khan's course for months rn and I get stuck for a weeks on a unit it's pretty hard since sometimes he's videos doesn't explain all the thing. So is there any way I can improve

[@Anime_World1168]

yes i got that

[@unravel9716]

I really don't understand but then I also can't point out what part it is that I'm not getting :( already screwed for my unit 1 paper it's in May

[@zhelyo_physics]

happy to explain things further if you find a point where it doesn't make sense. I think once you have practiced resolving the gravitational force in parallel and perpendicular components, it should be better. Best of luck!

[@alliancegaming2k585]

Sir, I have a question for you how can I send it to you?

[@zhelyo_physics]

there is a contact page on my website

[@alliancegaming2k585]

@@zhelyo_physics Thank you Sir.

[@Blaze_Oblivion__]

If F = m × g × sinTheta + f, doesn't that mean that the car is not moving, since the forces balance out ?

[@endgamez7621]

newtons first law states an object will remain at rest or constant velocity unless acted by a resultant force; so it could move if both forces were equal, in this example it's not accelerating

[@aleksandarjankovic1531]

No. It just means it will continue moving at constant speed i.e acceleration is 0.

[@zhelyo_physics]

Excellent answers! And yes, if all the forces are balanced it means that the acceleration is 0. But the car can still be moving. Hope this helps!

[@r3ma1n36]

legend

[@zhelyo_physics]

thank you!

[@moussaginoboateng5574]

Wouldn’t the weight (gravity) force on the slope be mg/sinx instead of mgxsinx 2:22

[@PrinceEntrapto]

No, you would only really do that (mg/sinTheta) if you were looking for an unknown quantity relating to circular motion, like tension on a string

[@zhelyo_physics]

Excellent answer! In this situation we have to resolve the weight into vertical and horizontal component. Further explained and derived here: kzbin.info/www/bejne/faLcemawoZ6DldEsi=Icxxr6sfEQmQPrWI

[@yussufdualeh1804]

doesnt distance equal to velocity times time so power should equal to force multiplied my velocity times time

[@greenjars_]

P = Fv, what you are describing is P = Fs or P = Fd? Both of those equations don't describe power but work done △W.

[@zhelyo_physics]

@greenjars_ is precisely correct! Well explained. So Work Done/time = Fx/t=Fv=power. Hope this helps!

[@yussufdualeh1804]

makes sense just realised tht@@greenjars_

[@mizukun9037]

Im taking caie AS physics, u have 20 days left and i feel like i barely know anything at all, how should i go sbout now

[@zhelyo_physics]

you got this! This playlist will help, well the first half of it is for AS Level. kzbin.info/aero/PLSygKZqfTjPC3hJ7nRSnnXTw3tI_o67dR&si=opB6y581HR9Soc_b

[@mizukun9037]

@@zhelyo_physics thanks also I meant to say " I "

[@macman3749]

Hi sir, could please solve this question regarding malus law ? 9792/02/M/J/19 qno.6. it can prevent students from getting an A*.

[@Sarandazz]

I just realised u kinda look like Stephen hawking lol

[@zhelyo_physics]

I'll take that! : ) If I could only revolutionise our understanding of the universe next!

[@Endermanv-ot2if]

sir can you sit ocr a level physics this summer to see if u can get an A* @@zhelyo_physics

[@Preetdutt0909]

I did that question ❤ before you

[@zhelyo_physics]

Amazing!

[@JujutsuMath]

nice video

[@zhelyo_physics]

Thank you!

[@JujutsuMath]

@@zhelyo_physics I have IB physics exams coming up in about 30 days, could you do a video going through a paper ? they're really unique in the question types especially paper 1 you might enjoy :)

[@Liszth_]

🤔🧠 🤓