(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An aircraft of mass 5.8 x 10^4 kg stands at the end of the runway ready for take-off. The engines provide a constant total thrust of 2.1 x 10^5N

i)Calculate the initial acceleration in ms-2 of the aircraft as it starts to move

ii) Calculate the length in m of runway needed for the aircraft to reach its take off speed of 85 ms-1 , assuming acceleration is constant

2. Relevant equations

Motion Equations

v = u + at

s = (u + v)/2 * t

s = ut + 1/2*at^2

3. The attempt at a solution

The answer is 3.6ms to part i) but i cant seem to get anywhere near that.

I really dont know where to start.

Do i square both numbers and square root it? I just need a guide to lead me what info i have and what info i need.

thank you

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Motion - V.Confused!

**Physics Forums | Science Articles, Homework Help, Discussion**