4ESO Física i Química : ARTICLE 123 : Forces and dynamics.
- Check the following link to begin the next lesson about how forces act :
4ESO Física i Química : ARTICLE 122 : UNIFORM CIRCULAR MOTION PRACTICE.
- At this article will be hung pictures and video about uniform circular motion practice we did yesterday using the skates :
> VIDEO.
4ESO Física i Química : ARTICLE 121 : CIRCULAR MOTION EXPERIENCE, LINEAR AND ANGULAR VELOCITY.
- This is a little drawing about the practice we have done of the uniform circular motion with our skates using a spinning movement at the playground.
On friday well check the times and data we have taken and will work out angular velocity and will talk about all of this.
1ESO Tecno : ARTICLE 13 : Les Escales.
4ESO Física i Química : ARTICLE 120 : Free fall complexer exercise.
- Try to do this exercise. If you cannot achieve it, watch the video and look at and listen to the explanation, but try first doing it without watching the video :
> Exercise :
A Stone is thrown from the top of a building with an initial velocity of 20m/s straight upward. The building is 50m high, and the Stone just misses the edge of the roof on its way down. Determine :
a) The time needed for the Stone to reach its máximum height.
b) The máximum height.
c) The time needed for the Stone to return to the level of the thrower.
d) The velocity of the Stone at this instant.
e) The velocity and position of the Stone at time = 5 secons.
4ESO Física i Química : ARTICLE 119 : UNIFORM CIRCULAR MOTION.
- Let's look the following link up in order to learn about circular motion :
4ESO Física i Química : ARTICLE 118 : FREE FALL MOTION exercises.
- Watch the following video and later we will do a similar exercise all together :
- Watch the previous video and the next ones you find below and try to do the following two exercises at home : (you still have the videos with the solution in case you dont know how to finish them).
1- Problem 1 :
a) A child throws just upright to the sky a little stone with a starting velocity of 6 m/s. Find the time the Stone takes to reach the higher position.
b) After that, work out the distance this stone goes over when it finally hits the ground at the end of its movement. How long does the Stone take to arrive again to the ground from its higher position on the top?.
c) Work out the total displacement the stone does from the beginning to the end of its movement and the total time of this movement from the beginning to the end.
2- Problem 2 :
From the top of a skyscraper a stone is thrown in a straight line motion to the ground with a starting velocity of 2 m/s. if the stone takes 5 seconds to hit the ground, work out how high the skyscraper is.
(There is a mistake at the video because , as the Stone goes down some direction to gravity, the starting velocity must have same sign as gravity, if I write minus sing for gravity I must write also minus sign for starting velocity.
I should have written - v0 instead of + v0 for the starting velocity.
So It must be written : 0 = h - v0.t - 1/2.g.t2 ).
Then the skyscrapers high is : h = 10 + 1225 = 1325 m
Once you have tried to do these exercises and watched the videos, will you do a few more similar exercises next Friday in class. Then it is important you do at home the suggested activities on this article 118.
DONT FORGET TO DO THIS AT HOME!!!
- Now that you have watched all these videos and last friday you have also tried a few more similar exercises in class, try now a few more ones like that at home as homework :
Do exercises 43, 27, 58 and 59 from your book and have them ready on Monday.
4ESO Física i Química : ARTICLE 117 : Students' canvas posters and their videos explanations.
- Our students explain in these videos , throughout a canvas poster, what they consider as most important since they are studying the chemistry and physics subject this course :
> Angels canvas video.
> Marinas canvas video.
Marinas canvas poster can be seen on detail here.