# How to calculate thrust

• fleur

## Homework Statement

The lorry starts from rest with an acceleration of 2 ms-2.
What is the effective thrust is being exerted?

## Homework Equations

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

## The Attempt at a Solution

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

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

• fleur