# How to calculate thrust

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1. May 16, 2016

### fleur

1. The problem statement, all variables and given/known data
The lorry starts from rest with an acceleration of 2 ms-2.
What is the effective thrust is being exerted?

2. Relevant equations
acceleration=2 ms-2
starts from rest so initial velocity =0 ms-1

3. The attempt at a solution
F=ma

2. May 16, 2016

### Staff: Mentor

You'll need to provide the mass of the lorry. That will be the "m" in your f = ma.

3. May 17, 2016

### fleur

The mass is 28000kg,so 28000x2=56000 N
would i just multiply it by the acceleration of 2 ms-2 but what about the acceleration due to gravity

Last edited: May 17, 2016
4. May 17, 2016

### Staff: Mentor

Presumably the motion that is of interest here is in the horizontal direction, and the lorry is accelerating along a level road surface. Gravity operates in the vertical direction, and the road surface prevents motion in that direction. The vertical force due to gravity (weight) does not contribute to motion in the horizontal direction.