# Help with M1 question

Announcements
#1
At time t = 0, two balls A and B are projected vertically upwards. The ball A is projected vertically upwards with speed 2m/s from a point 50m above the horizontal ground. The ball B is projected vertically upwards from the ground with speed 20m/s. At time t = T seconds, the two balls are at the same vertical height, h metres, above the ground. The balls are modelled as particles moving freely under gravity.

I've got to the point where I have two equations:

Ball A -
h-50=2T+1/2(-9.8)t2

Ball B -
h=20T+1/2(-9.8)t2

What do I have to do now to solve h and T?
0
#2
Any help will be appreciated!
0
5 years ago
#3
(Original post by ℓove)
At time t = 0, two balls A and B are projected vertically upwards. The ball A is projected vertically upwards with speed 2m/s from a point 50m above the horizontal ground. The ball B is projected vertically upwards from the ground with speed 20m/s. At time t = T seconds, the two balls are at the same vertical height, h metres, above the ground. The balls are modelled as particles moving freely under gravity.

I've got to the point where I have two equations:

Ball A -
h-50=2T+1/2(-9.8)t2

Ball B -
h=20T+1/2(-9.8)t2

What do I have to do now to solve h and T?
This is simply simultaneous equations, and so, assuming your equations are correct, we can subtract Ball A from Ball B, giving:

h-(h-50)=20T+1/2(-9.8)T2 -(2T+ 1/2(-9.8)T2)

50=18T

T=50/18

Then we can solve

h=20*T+1/2(-9.8)T2 plugging in our T value

1
#4
(Original post by mathematigeek)
This is simply simultaneous equations, and so, assuming your equations are correct, we can subtract Ball A from Ball B, giving:

h-(h-50)=20T+1/2(-9.8)T2 -(2T+ 1/2(-9.8)T2)

50=18T

T=50/18

Then we can solve

h=20*T+1/2(-9.8)T2 plugging in our T value

Thanks!!!!!
1
1 year ago
#5
simplify and solve simultaneously
0
X

new posts Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### How did your AQA A-level Physics Paper 1 exam go?

Great! Feeling positive (28)
26.92%
It went fairly well (45)
43.27%
It didn't go too well (19)
18.27%
TERRIBLE! (12)
11.54%