In some SUVAT questions, they ask for 2 time solutions and I can only find 1. What am I missing?

Let's say we are trying to work out how long it will take for a ball to be caught after it has been thrown straight upwards. If we set the final displacement to be zero (S=0) and solve S=UT+0.5AT2, it appears that we only get one value for T. However, there will always be a step in your workings when you can cancel a T from both sides of the equation, for example: 5T2 = 100T can be simplified to 5T = 100. In this step, we miss out a solution that T=0! This corresponds to when the ball is just about to be thrown so is still in our hands (hence we have a solution for zero displacement!)

CI

Related Physics A Level answers

All answers ▸

A projectile is launched from the ground at a speed of 40ms^-1 at an angle of 30 degrees to the horizontal, where does it land? What is the highest point the projectile reaches?


Describe one technique you could use to measure the threshold voltage for LEDs.


Please explain how polarisation of waves occurs?


A small ball of mass 150 g is placed at a height of 20cm above the ground on an incline of 35°. It is released and allowed to roll down the slope; what will be the ball's speed when it reaches the ground? Assume friction and air resistance can be ignored.