Mathematics: Post your doubts here!

[i_try9621]

View attachment 60372

This could help.

 

[i_try9621]

For part b why dont we use d sin theta over here?
Also if resistive forces were given will we use d or d sin theta?
View attachment 60373

They asked for the work done by the driving force while travelling on the slope(which is 800 m). If you take d sin(theta), it gives you the vertical distance between the slope and the ground .

 

[funky brat]

They asked for the work done by the driving force while travelling on the slope(which is 800 m). If you take d sin(theta), it gives you the vertical distance between the slope and the ground .

Yeah alright. Thank you

 

[i_try9621]

View attachment 60374 Anyone?

this could help .

 

[funky brat]

Why is the encircled part done in the MS? Why couldn't it simply be 0.4g-1.4=0.4a

 

[funky brat]

View attachment 60380 View attachment 60381 View attachment 60382 this could help .

Thanks.

 

[i_try9621]

View attachment 60387 View attachment 60388
Why is the encircled part done in the MS? Why couldn't it simply be 0.4g-1.4=0.4a

• find sin (theta) from the equation .
• using newton's second law , ( 0.4g x sin(theta)) - 1.4 = 0.4a

 

[funky brat]

View attachment 60390

• find sin (theta) from the equation .
• using newton's second law , ( 0.4g x sin(theta)) - 1.4 = 0.4a

Oh alright. Thanks.

 

[funky brat]

2nd part.

 

[Lola_sweet]

can someone do part ii?

 

[Rizwan Javed]

can someone do part ii?

Something like this^

 

[Lola_sweet]

View attachment 60395
Something like this^

how do you know between 0 and π symbol curves like that?
im sorry for such a stupid qs

 

[i_try9621]

2nd part. View attachment 60393

• distance of P1 = 25 + distance of P2
• using s = ut + 1/2 at^2 , find the time
• using v = u + at where a is 10 ms^-2 , find the velocities

 

[i_try9621]

how do you know between 0 and π symbol curves like that?
im sorry for such a stupid qs

http://www.intmath.com/trigonometric-graphs/1-graphs-sine-cosine-amplitude.php this could figure your doubt out.
And also this http://www.purplemath.com/modules/grphtrig.htm

 

[Lola_sweet]

http://www.intmath.com/trigonometric-graphs/1-graphs-sine-cosine-amplitude.php this could figure your doubt out.
And also this http://www.purplemath.com/modules/grphtrig.htm

thank you

 

[Rizwan Javed]

how do you know between 0 and π symbol curves like that?
im sorry for such a stupid qs

The normal sine curve is like this:


But when there's a negative sign with sine, the curve is inverted like this:

 

[Lola_sweet]

The normal sine curve is like this:
View attachment 60397

But when there's a negative sign with sine, the curve is inverted like this:
View attachment 60399

thank you so much rizwan
today i annoyed u a lot

 

[The Sarcastic Retard]

6 is in numerator and u didnt multiply it after u expanded them?

I did multiply

 

[mohmed ahmed soliman]

i took complete the square but what is this

 

[Rizwan Javed]

the curve instersects with y axis at 1 so a is 1 but how to find b which is 2 in mark scheme
View attachment 60407

b here is the amplitude of the curve. Amplitude is the maximum distance from the mean line. Here you can see that amplitude of the sine curve is 2 from the mean line.