Hey Kevin!, i have a question 🙋 If i threw an object upwards from the top of the building does it take the same amount of velocity to get back to me (still on top of the building) as it did to get to its maximum height? (Btw your 50 questions video on sequences and series was the best thing ever 😆 got me 46/50 on a test 😁 and maths is not my strong point )
Hello sir. 👋 In the second example, when calculating final velocity, I chose up as positive that meant my acceleration and displacement was negative. I got a positve final answer, so my question is, would I say the final velocity is 29,83 m/s in the upwards?
I also got the same answer, but I figured out that it is because the ball will bounce upwards with the calculated velocity as it already made contact with the ground.@@lengwengvillakazi5193 👍
hey @kevinmathscience. i have a question chose up as positive for the second question and i got my answer as a positive so does that entail that my velocity would be upwards, if yes, when i used it as a positive with the time question i got t=-1,02
Sir we really appreciate ur videos 🥺❤️❤️💯💯 could you pls make a video of ur self , so that we can know more about you🥺🥺🙏🏻🙏🏻🙏🏻but all in all you are really amazing.
Good day sir, I love your courses! They make an excellent form of practice especially now for finals. Thank you so much for posting! I was curious as to why you had only calculated the time for the ball falling from the length of the building (last question). I was sure that you had to work out how long it takes for the ball to "crest" aswell and then combine the two answers....Am I missing something? I got the total time as 9.16 seconds...
@@abhayajoodha2331 hi there Did uu end up getting the answer he got? I just did the question, but I chose up as positive and both my answers are incorrect. I chose up as positive in the first question and my answers are correct. If uu can please explain. If uu don't mind of course:)
Hi I wanted to ask why did you add the initial velocity to the final velocity for the second question in which that resulted to 29.49 because the answer I am getting is 9.49
Good day, sir. I have a question. In the second section of questions, on question 2, when we calculate the time, why did you not use the third formula which has ∆x (displacement)? Instead you used the first formula.
I first calculated the distant above the building then I added it to the equation you gave me with the distance of the building and still got the same answer ???!
So SIR in example 2 A our displacement must be negative if we chose upwards as positive because if i don't put negative it gives me 9,49 which is different from your answer
If you choose down as negative, then you will still get correct answer but you must use correct signs. So If down as negative. vf = vi + a*t -29.83 = 20 + (-9.8)*t t = 5.08s
Yes so you would use: delta x = vi*t + 0.5a*t^2 Let us imagine I choose down as positive: 25 = -20t + 0.5 (9.8)t^2 Then move everything to one side and make the other side = 0 Then use normal quadratic formula. 0 = 4.9t^2 - 20t - 25 a = 4.9 b = -20 c = -25 If up is positive: -25 = 20t + 0.5 (-9.8)t^2 Then move everything to one side and make the other side = 0 Then use normal quadratic formula. 0 = -4.9t^2 +20t + 25 a = -4.9 b = 20 c = 25
i really hope your channel blows up because you're an amazing teacher....this is super helpful
I am so happy that this has helped you! All the best Kealeboga!
I've been watching you for 2 years i need to be consistent with watching your content
Example 2 A i got Vf= 9.49 m.s`¹
Hey Kevin!, i have a question 🙋
If i threw an object upwards from the top of the building does it take the same amount of velocity to get back to me (still on top of the building) as it did to get to its maximum height?
(Btw your 50 questions video on sequences and series was the best thing ever 😆 got me 46/50 on a test 😁 and maths is not my strong point )
Will you be doing a video on graphs for this section anytime soon..?🙂
Hello sir. 👋 In the second example, when calculating final velocity, I chose up as positive that meant my acceleration and displacement was negative. I got a positve final answer, so my question is, would I say the final velocity is 29,83 m/s in the upwards?
Can someone please answer😢
I'm confused too😢😢😢😢
I also got the same answer, but I figured out that it is because the ball will bounce upwards with the calculated velocity as it already made contact with the ground.@@lengwengvillakazi5193 👍
Same
Same here
hey @kevinmathscience. i have a question chose up as positive for the second question and i got my answer as a positive so does that entail that my velocity would be upwards, if yes, when i used it as a positive with the time question i got t=-1,02
I also got the same answer as you
Same
Me too
Sir we really appreciate ur videos 🥺❤️❤️💯💯 could you pls make a video of ur self , so that we can know more about you🥺🥺🙏🏻🙏🏻🙏🏻but all in all you are really amazing.
Yes I will do this some time :)
At example 2 I took direction up as positive and I got a different answer from 29.83
Nanne
yeah,i got 12.45
@@shudumutepe4768 same
I got 29,83 but my direction was up not down
@@Hl0_nisame😢😢😢
Good day sir, I love your courses! They make an excellent form of practice especially now for finals. Thank you so much for posting!
I was curious as to why you had only calculated the time for the ball falling from the length of the building (last question). I was sure that you had to work out how long it takes for the ball to "crest" aswell and then combine the two answers....Am I missing something? I got the total time as 9.16 seconds...
Hello Abhay, please go through the video carefully once more as I do explain that exact part as it does confuse many learners.
@@kevinmathscience thank you sir, I get it now, "Displacement"...
@@abhayajoodha2331 hi there
Did uu end up getting the answer he got? I just did the question, but I chose up as positive and both my answers are incorrect. I chose up as positive in the first question and my answers are correct. If uu can please explain. If uu don't mind of course:)
Hey Kevin, can I ask, for A) why did you add 'down' at the answer?
thank you kevin
Hi
I wanted to ask why did you add the initial velocity to the final velocity for the second question in which that resulted to 29.49 because the answer I am getting is 9.49
It all has to do with direction. Please check that part carefully again :)
I chose the same direction as you did. But the error you made was probably w the displacement.
The right answer is 29.83
i also done the same and got 9.49
@@ushbaasad3559 your displacement must be negetive
Thanks Kelvin I was really lost and had no idea what to do or what to apply 🙈
So happy it helped :)
But why if we choose up to be + then we get 9.49 for A
i got the same answer
If you choose upwards as positive, the displacement should also be negative
But he mentined in the other video that displacement should not be negative @@ntshiengnhlapo5677
If I choose down as negative my disp (-) and a (-) vi(-)
But why the answer is positive while down its negative .?
Damn bro, He didn't explain that but thanks man 🤝🏽@@ntshiengnhlapo5677
God bless you man, why don't you open a school bro😭👏👏
Sir kev what about the time it took to go up and come down ?
Good day, sir. I have a question. In the second section of questions, on question 2, when we calculate the time, why did you not use the third formula which has ∆x (displacement)? Instead you used the first formula.
Hello, you could have used that as well :) Both would work :)
where could I find the horizontal projectile motion videos?
I first calculated the distant above the building then I added it to the equation you gave me with the distance of the building and still got the same answer ???!
So SIR in example 2 A our displacement must be negative if we chose upwards as positive because if i don't put negative it gives me 9,49 which is different from your answer
In the second question I took down as negative and got different answers, I see how direction affects the calculations
If you choose down as negative, then you will still get correct answer but you must use correct signs.
So If down as negative.
vf = vi + a*t
-29.83 = 20 + (-9.8)*t
t = 5.08s
Kevin please do A using down as negative, you'll se that the velocity is still positive, so does that mean the direction is upwards
@@keabetswemotsamai4011true😢😢😢
so if we had to find the time, and we choose that other formula (with the ½ involved)... we'd have to do it in a quadratic manner. please show how
Yes so you would use:
delta x = vi*t + 0.5a*t^2
Let us imagine I choose down as positive:
25 = -20t + 0.5 (9.8)t^2
Then move everything to one side and make the other side = 0
Then use normal quadratic formula.
0 = 4.9t^2 - 20t - 25
a = 4.9
b = -20
c = -25
If up is positive:
-25 = 20t + 0.5 (-9.8)t^2
Then move everything to one side and make the other side = 0
Then use normal quadratic formula.
0 = -4.9t^2 +20t + 25
a = -4.9
b = 20
c = 25
Hey Kevin on A on the first question im getting 490
you must put square root
good day sir isnt 9.8 supposed to be a negative?
It all depends on direction choice :) So if you choose up as positive then it is -9.8 but if you choose down as positive, then it is 9.8 :)
@@kevinmathscience sorry sir is my will my answer be wrong if I choose up as positive?
But i get my final answer for question A as 9,49
Same
Sir on the second one i took down as a negative and I got Vf as 9,49 downwards
Sorry but just to clarify
Vi = 0 when dropped ??
Yes correct :)
@@kevinmathscience just wanted to say sir, I wrote my physics exam today and it's all because of you I'm confident I passed well 🔥❤️