What are the most difficult M1 questions you have come across?

Q3 on this paper. It is great fun!

It tests almost everything you need to know for pulleys and scale pans

Preferably edexcel.

Also had good question here.

A ball is projected vertically upwards from a point $O$ with a speed $u$m/s. At the same time a second ball is dropped from a height of 40m vertically above $O$. Given that the balls have the same speed when they collide, find the time at which they collide.

Do you have the mark scheme for that, I tried to do it but I ended up with two times of -0.58s and -3.5 seconds

Do you have the mark scheme for that, I tried to do it but I ended up with two times of -0.58s and -3.5 seconds

You could post your working and we can check it.

Solution in spoiler.

Preferably edexcel.

ahh sound, i think i just messed up one of my substitutions in my first attempt.

Here is a link to some resources made by the user TeeEm.

Now you can do it you should pray that a similar question comes up in the real thing!

You would be part of a small minority who could do it.

Preferably edexcel.

That looks good.

Do you know where I can find a complete definition list for M1.
The only one I have is blank.

Here is a powerpoint with all of that info

Sure, I did it again and this time I got 10/7 seconds, although I'm not sure wha tthe correct solution is.

why is it s-40 and not 40-s, s-40 will give you a negative distance?

Well that depends on which direction you take as positive.

Negative displacement is fine since it's a vector quantity.

But you're right that there is a mistake in the working. One of the displacement equations uses negative acceleration and the other uses positive.