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Thanks for the comments , appreciated.

Thanks for the comment, appreciated.

Feel free to ask if you have any questions .

Thanks ,appreciated.

In a printable format if possible.

Thanks , all A2 Physics mindmap are available in pdf format on Patreon . Please check A2 Physics Mindmap folder on Patreon .

dsin*angle=n* Wavelength , it's very clear that d affects the angle or fringe spacing . Imagine a diffraction grating of length 1 cm and it has 10 slits so d = 0.1 cm . Now imagine that we have diffraction grating of 2cm and there are 20 slits so again d=2cm/20=0.1 cm . As long as d is same , N does not affect . Hope it makes sense . You can watch solution again for better understanding .

Feel free to ask if you still have any questions .

Total weight of sphere , probe and string =5N+2N=7 N , as sphere is in equilibrium it means that Weight = Upthrust =7 N . As question said upthrust due to probe and thread is negligible , it simply means that MOST of the upthrust is due to sphere only . In this case upthrust due to probe and string is negligible because they have very very small volume as compared with volume of sphere . Hope it makes sense . For better understanding , you can listen explanation again . Let me know if you still have any questions .

Smaller diameter and greater length , produces more extension so answer for question 3 should be C . Hope it helps , let me know if you have any questions .

Thanks , appreciated .

Glad it helped,thanks .

Thanks for comments , appreciated .

In this case , D is constant and also question states that keep fringe spacing same i.e. x remains same . Question also says that what change should be made to slit separation so that fringe spacing remains same i.e. keep D constant . Hope it helps . Let me know if you still have any questions .

⁠​⁠​⁠​⁠@@alevelandapphysics-alibut like isn’t this part of question e). It states no where in d) that the we should keep slit separation the same… part d) only says without changing frequency

@@Floprieeee73 It's for part e and in part d ) we are only changing light frequency so rest of the variables should be kept constant that's reason slit separation and D are constant . If frequency is constant then fringe spacing also remains constant . Hope it makes sense now . If you watch video solution , it will give you better understanding .

No.of sf in final answer should be equal to LEAST no. of sf in given data but at AS level if you use 2 or 3 sf it's acceptable except when question says use appropriate no.of sig figs in the answer . Then no. of sf in your final answer should be equal to LEAST no. of sf in given data in the question . Hope it helps .

Smaller than half of a small square.

@@alevelandapphysics-ali but sir that would be almost the thickness of my actual line? Doesn’t the accuracy to smaller than half a square mean I can plot my point in a range less than half a square from the actual value like if it would be in the white margin I place it on the grid which is less than half a square away?

@@connor__schmitz4619 I mean the thickness of dot ( centre of cross i.e intersection of two lines ) . It should be less than half a small square . Don't make it too thick , if use sharp pencil it should be fine .

@@alevelandapphysics-ali ohh i see so the actual thickness of the cross may be slightly larger but the intersection needs to be half a small square, thank you🙌

Most welcome

Charge takes the path of LEAST resistance , as ideal wire has zero resistance so whole charge goes through wire as the resistance of 5 Ohms is much much greater than zero resistance . Hope it helps , feel free to ask if you still have any questions .

@@alevelandapphysics-ali ok so i guess its an unspoken rule that charge always passes through where theres less resistance when in parallel correct? thanks

@@gustybot As a thumb of rule , if a wire is connected in parallel with any resistor then most of the charge passes through wire or simply that resistor is shortend ( no current through resistor ) .

Thank you!!

Glad it was helpful , feel free to ask if you have any questions and share channel with friends if possible .

Most welcome, thanks .

Glad it was helpful , let me know if you have any questions .

Blue light has higher frequency than red light . Higher frequency , higher energy of each photon . As intensity is constant so fewer number of photons . Please watch solution again , it will make better sense now .

Mass of single nucleon =1 u , u= atomic mass unit . Mass of 215 nucleons = 215 u . Hope it helps .

@@alevelandapphysics-ali okay got it. Thanks

Glad it helped

Gradient of I-t graph is negative . so emf is positive ( negative of negative gradient ) . As Gradient of I-t graph is decreasing with time so graph should be decay graph . Hope it helps . Let me know if you still have any questions .

@@alevelandapphysics-ali thank you. Understood

Glad it helped

Glad you liked it .

Glad it was helpful , feel free to ask if you have any questions .

As weight is acting vertically downwards so it has no horizontal component . Centripetal force is provided by horizontal component of tension . Vertical component of tension = Weight . Hope it helps , let me know if you still have any questions .

@@alevelandapphysics-ali thank you sir🙏🏽

Glad it helped!

Glad it helped .

Yeah ,if terminals (or ends ) are connected it will form a closed loop .

@@alevelandapphysics-ali so closed loop will cause an induced current to flow if there is an induced emf right? if not closed no induced current flow right

@@你很牛 That's right , you got it .

Magnetic force is due to perpendicular component only that'sreason F=BILsin(x) .

If current in the wire and magnetic field are in the same direction so no magnetic force .

@@alevelandapphysics-ali thats meant although they might not be perpendicular but the force acted must be perpendicular?

@@你很牛 Magnetic force is always perpendicular to Current and Magnetic field direction .

Hope it helps , let me know if you still have any questions .

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@@alevelandapphysics-ali English mass, Sunday 12 noon?

@@lovejoseph1899 yeah .

Dotted or normal lines are both acceptable .

@@alevelandapphysics-ali oh alright thank you🙌

Coz we are calculating magnitude of mean induced emf .The minus means that the emf creates a current I and magnetic field B that oppose the change in flux ΔΦ - This is Lenz's law .

ohh that makes way more sense thank you🙌

So nice of you, thanks and appreciated .

Electrostatic force or electric force both acceptable .The electric force between stationary charges is conventionally known as the electrostatic force or Coulomb's force. Conductors oppose the change in magnetic flux that's reason opposite magentic poles are produced to oppose the change in flux and force between ring and coil is repulsive .

@@alevelandapphysics-ali thats meant it will only happen for a while? as i am confusing at it didnt move and lenz law state that is opposing the motion.that producing the emf.

@@你很牛This will happen until flux is changing i.e. flux is increasing due to increase in current in the coil . In this case , ring will move upwards due to repulsive force . Hope it makes better sense .

@@alevelandapphysics-ali so it is like when the current flow this cause the build up of magnetic field in the coil and at the same time an induced current is flow in the copper when the current is flow in coil as there is a change in magnetic flux and this result in the opposing force ?

You're almost there , Increase in current in the coil causes increasing magnetic field . Due to this increasing magnetic field , magnetic flux in the ring increases to oppose the increase in magnetic flux , current flows in the ring which produces its own magnetic field to oppose the external magnetic field due to increasing current . The interaction between two magnetic fields causes opposing magnetic force .

In this case , we are calculating initial upward acceleration and balloon started from rest i.e. v=0 so Drag can be ignored . Hope it helps .

Glad to hear that

When it's in free fall its acceleration =g=9.81 m/s^2 and it's only true while falling but when it hits the ground it's not in free fall coz there is a force from the ground so its acceleration is different as shown by the graident of v-t graph . Hope it helps . Feel free to ask if you still have any questions .

@@alevelandapphysics-ali ohhh ok thanks, my exam is in 3 hours please wish me luck

@@gustybot All the best today's exam and coming exams .

As there is a net force (electric force ) on charged particle so it has acceleration and its horizontal velocity is not constant .

Terminal velocity means final constant velocity so when object reaches terminal velocity forces are balanced so Weight = Drag force as weight is constant so Drag force is also constant at any terminal velocity . In the second case , as viscosity decreases so terminal velocity should increase . Hope it makes better sense now .

For better understanding you can watch solution again .

@@alevelandapphysics-ali thank you sir i understood

Current is the amount of charge passing through a point per unit time so direction of current is in direction of flow of charge / charged particle i.e. sphere in this case .

Electric field lines tell us direction of force on positively charged particle if charged particle is in the electric field . Hope it makes sense . Feel free to ask if you still have any questions .

@@alevelandapphysics-ali so sir in this case the electric field line is not the way current flowing? it is only due to positive and negative charge right?

@@你很牛 That'sright .

Coz numbers are more manageable and easier to plot by taking 100 =10^2 common e.g. 400 can be written as 4 *10^2 , 1000 can be written as 10 *10^2 and so on . Hope it makes sense and feel free to ask if you have any questions .

sure , if you have any questions .

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