MedVision ad

Projectile Motion help! (2 Viewers)

Chicken Burger

New Member
Joined
Dec 3, 2012
Messages
25
Gender
Male
HSC
2014
A ball is thrown upwards at an angle of 30 degrees to the horizon with an initial velocity of 50 m/s. Calculate the:
a) height it rises
b) horizontal distance to impact
c) time to impact

Thanks
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
a) For maximum height, we let dy/dt=0, and you will get t = ...

Sub that t = ... back into your y = (something in terms of t) for maximum height.

b) For horizontal distance, let y=0 and similarly to above, you will get t = ...

Sub that t = ... back into x = (something in terms of t) for horizontal distance.

c) You already found time to impact by letting y=0 and solving for t in part (b).

====================================================

EDIT: Never mind this post. I did not notice that it was in the Physics section, not MX1.
 
Last edited:

Chicken Burger

New Member
Joined
Dec 3, 2012
Messages
25
Gender
Male
HSC
2014
But can we use this method on a physics exam? Because I haven't learnt your method in physics...
 
Last edited:

Secant

Member
Joined
Mar 30, 2013
Messages
37
Gender
Male
HSC
N/A
wait, why is there differentiation? I don't remember differentiation being in physics projectile motion topic 1 space?
you don't do MX1 do you?

EDIT: ~peace out homie~
 
Last edited:

Chicken Burger

New Member
Joined
Dec 3, 2012
Messages
25
Gender
Male
HSC
2014
plus i dedicated most of my time in mx1 and mx2, rarely for physics.. which is bad...
 

Secant

Member
Joined
Mar 30, 2013
Messages
37
Gender
Male
HSC
N/A
A ball is thrown upwards at an angle of 30 degrees to the horizon with an initial velocity of 50 m/s. Calculate the:
a) height it rises
b) horizontal distance to impact
c) time to impact

Thanks
a) max height: use v^2=u^2+2as (it is on the syllabus) then sub v=0, u= 50sin30 and a=-9.8 continue
b) find t using s=ut+1/2at^2 by making s=0, then use x=u(x)t, x is the range
c) u already found the time.

EDIT: ~peace out homie~
 
Last edited:

Secant

Member
Joined
Mar 30, 2013
Messages
37
Gender
Male
HSC
N/A
i do mx1 and mx2, but we havent covered simple harmonic
it is under 'projectile motion' in mx1 but you DO NOT need mx1 in physics and if you use mx1 you get it wrong (i think), the formulas are given to you on the syllabus and the formula sheet in the exam so just sub in and get the answer you want

EDIT: ~peace out homie~
 
Last edited:

Chicken Burger

New Member
Joined
Dec 3, 2012
Messages
25
Gender
Male
HSC
2014
a) max height: use v^2=u^2+2as (it is on the syllabus) then sub v=0, u= 50sin30 and a=-9.8 continue
b) find t using s=ut+1/2at^2 by making s=0, then use x=u(x)t, x is the range
c) u already found the time.

EDIT: ~peace out homie~
hey secant can you tell me why v=0?
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
Oh my fault! I thought this was in the Mathematics section, so I gave an answer using methods from MX1.
 

yasminee96

Active Member
Joined
Sep 8, 2012
Messages
346
Gender
Female
HSC
2013
i got told that using the notation in mx1 would make you lose marks. That's what i was using the whole time but apparently it makes a huge difference if you write x instead of delta x dafuq. yeh, stick to physics formulas - but they're exactly the same as mx1, just different notation, and you derive formulas in mx1 :)
 

Chicken Burger

New Member
Joined
Dec 3, 2012
Messages
25
Gender
Male
HSC
2014
hey guys another question sorry.
A basketballer projects a ball at an angle of 30 degrees to the horizontal at 9.8 m/s.
What will be the impact velocity and its direction?
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top