• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

Physics Predictions/Thoughts (3 Viewers)

scaryshark09

∞∆ who let 'em cook dis long ∆∞
Joined
Oct 20, 2022
Messages
1,618
Gender
Undisclosed
HSC
1999
For people who do physics, definitely including @scaryshark09 , do we need to know equation examples of alpha, beta and gamma decay off by heart? Can they ask us to give an example??
i would say it is best to learn these equations off by heart.
they can ask to give an example
 

skp_mp4

New Member
Joined
Jul 10, 2023
Messages
5
Gender
Male
HSC
2023
How much yall reckon is gonna be good enough for a band 5 gonna be this year
 
Joined
Jul 6, 2022
Messages
34
Gender
Female
HSC
2023
HELP PLEASE!
Screen Shot 2023-10-30 at 9.35.04 am.png

Screen Shot 2023-10-30 at 9.34.02 am.png
Screen Shot 2023-10-30 at 9.34.14 am.png
Screen Shot 2023-10-30 at 9.34.40 am.png

Does anyone know how to solve these questions? They're from the 2023 parramatta high school trial paper
Below are their answers:










10: B
13: A
14: B
 

Aaryan123

New Member
Joined
Nov 6, 2022
Messages
6
Gender
Male
HSC
2023
HELP PLEASE!
View attachment 41236

View attachment 41233
View attachment 41234
View attachment 41235

Does anyone know how to solve these questions? They're from the 2023 parramatta high school trial paper
Below are their answers:










10: B
13: A
14: B

for q10, you want to find a general formula for the range of a projectile. range occurs when the y displacement =0.
so from s=ut+1/2at^2, you let s=0. you also know that you can divide by t, because that is at the origin, we're looking for the t when it hits the ground again.
therefore, 0=usintheta+(1/2)(-9.8)t
hence t=2usintheta/9.8
now the range is the horizontal component multiplied by time travelled
so Range = Utcostheta
= 2U^2sinthetacostheta/9.8
= (u^2)sin2theta/9.8
now sub in all values given in options, and B should be the largest.

13. Use kepler's 3rd law, and remember that the r value that you find is the radius of the earth plus the altitude.
14. Remember that during uniform circular motion, the value of the centripetal accel is v^2/r. both v^2 and r are constant in this example, so accel is also constant hence B
 

CamdenCeccato

New Member
Joined
Oct 7, 2023
Messages
24
Gender
Male
HSC
2023
HELP PLEASE!
View attachment 41236

View attachment 41233
View attachment 41234
View attachment 41235

Does anyone know how to solve these questions? They're from the 2023 parramatta high school trial paper
Below are their answers:










10: B
13: A
14: B
There might be an easier way to do 10 but you calculate the time of flight for all the launches then find the range for all the launches.

i got d for 13 so I can’t help you with that one.
Don’t over complicate 14.
 
Joined
Jul 6, 2022
Messages
34
Gender
Female
HSC
2023
There might be an easier way to do 10 but you calculate the time of flight for all the launches then find the range for all the launches.

i got d for 13 so I can’t help you with that one.
Don’t over complicate 14.
for q10, you want to find a general formula for the range of a projectile. range occurs when the y displacement =0.
so from s=ut+1/2at^2, you let s=0. you also know that you can divide by t, because that is at the origin, we're looking for the t when it hits the ground again.
therefore, 0=usintheta+(1/2)(-9.8)t
hence t=2usintheta/9.8
now the range is the horizontal component multiplied by time travelled
so Range = Utcostheta
= 2U^2sinthetacostheta/9.8
= (u^2)sin2theta/9.8
now sub in all values given in options, and B should be the largest.

13. Use kepler's 3rd law, and remember that the r value that you find is the radius of the earth plus the altitude.
14. Remember that during uniform circular motion, the value of the centripetal accel is v^2/r. both v^2 and r are constant in this example, so accel is also constant hence B
thank you for this !
 
Joined
Jul 6, 2022
Messages
34
Gender
Female
HSC
2023
There might be an easier way to do 10 but you calculate the time of flight for all the launches then find the range for all the launches.

i got d for 13 so I can’t help you with that one.
Don’t over complicate 14.
you have to minus the radius of earth (6371km) from 6759.8, so 6759-6371km = 388.8 km and that's the answer
 

esybeast

Member
Joined
Apr 8, 2023
Messages
45
Gender
Undisclosed
HSC
2023
Screen Shot 2023-10-30 at 5.41.24 pm.png
Can someone explain why the answer is D and not C? (question from PHS)
 

Users Who Are Viewing This Thread (Users: 0, Guests: 3)

Top