A rocket travels at 500m/s two minutes after its take-off. If it was initially stationary, calculate its acceleration. If the rocket has a mass of 1800kg, what force is required to give it an acceleration of 2m/s^2?

  • Google+ icon
  • LinkedIn icon

a) Acceleration is the rate of change of velocity of an object

In this case, the equation that we will use to calculate it is 

a = (v - u )/ t

where v is the rocket's final speed, u is its initial speed, and t is the time taken

Note: units of measurement 

a: measured in m/s^2

v/u: measured in m/s

t: measured in s

Putting the given values into this equation, we find that 

acceleration = (500 - 0)m/s / (2x60)s = 4.17 m/s^2 (2dp)

- Hints: the initial speed of the rocket was 0 m/s at it was stationary to begin with, and we multiply 2 by sixty as we must convert time values from minutes into seconds. 

- I have included units in the calculation above- you dont need to do this at every stage of calculation but make sure you include units when giving a final answer!

b)  We can work out the second part of this question using Newtons's second law of motion F = m x a 

 F = 1800 x 2   = 3600 N ( or 3600 kgm/s^2) 

This law explains that the force (F) acting on an object is equal to the mass (m) of an object times its acceleration (a)

Dhrushee S. GCSE Maths tutor, 13 plus  Maths tutor, GCSE Economics tu...

About the author

is an online GCSE Physics tutor with MyTutor studying at St. Andrews University

Still stuck? Get one-to-one help from a personally interviewed subject specialist.

95% of our customers rate us

Browse tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss