x Turn on thread page Beta
 You are Here: Home >< A-levels

M1 June 2013 (R) Question 4 help watch

Announcements
1. Video's on this paper are impossible to find (idk why). Im completely struggling with Question 4 especially. The mark scheme 100% confuses me. Can someone help explain how to do Question 4 for the M1 June 2013 (R)? Much appreciated.

Here's the question:
At time t = 0, two balls A and B are projected vertically upwards. The ball A is projectedvertically upwards with speed 2 m s–1 from a point 50 m above the horizontal ground.The ball B is projected vertically upwards from the ground with speed 20 m s–1. At timet = 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. Find (a) the value of T, (5)
(b) the value of h.(2)
2. What have you tried so far?
3. (Original post by samb1234)
What have you tried so far?
Well i might sound a little stupid but I drew a diagram of the motion of the two particles. Then i came up with the equation. using s=ut + 0.5at^2

50 + h = 2T + 0.5 x -9.8 x T^2
and
50= 20T + 0.5 x -9.8 x T^2

I don't know if im doing alright so far and i have no clue where to go from here
4. Well the height they meet at will be the same. Therefore in the time it takes a to travel S m, b must have traveled 50+s m. This gives you two equations which you can then easily solve simultaneously. See if you can do it from there
5. (Original post by samb1234)
Well the height they meet at will be the same. Therefore in the time it takes a to travel S m, b must have traveled 50+s m. This gives you two equations which you can then easily solve simultaneously. See if you can do it from there
Yeah i found what T was that's 2.78.
im having troubles with finding what h is these equations confuse me the most.
If i plug in T to h=(2 x T) - (0.5 x -g x T^2)
, i get a negative number for h which is wrong.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: February 1, 2016
Today on TSR

University rankings 2019

Cambridge at number one

Poll

All the essentials

Student life: what to expect

What it's really like going to uni

Essay expert

Learn to write like a pro with our ultimate essay guide.

Create a study plan

Get your head around what you need to do and when with the study planner tool.

Resources by subject

Everything from mind maps to class notes.

Study tips from A* students

Students who got top grades in their A-levels share their secrets