Trouble finding the magnitude of a net force required.

AI Thread Summary
To find the net force required to accelerate an 800 kg rocket sled from rest to 1500 km/h in 2.1 seconds, the correct approach involves first converting the final velocity to meters per second, resulting in 416.7 m/s. The user initially misapplied the formula F=ma by confusing velocity with acceleration, leading to an incorrect force calculation of 333360 N. Understanding the significance of time is crucial for determining acceleration, which can be calculated using the formula a = (final velocity - initial velocity) / time. The correct acceleration must then be used in the force equation to find the accurate net force. The user ultimately identified their mistake in interpreting velocity as acceleration.
mcaustin
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Here is the problem I have:
1. A 800 kg rocket sled can be accelerated at a constant rate from rest to 1500 km/h in 2.1 s. What is the magnitude of the required net force?

First I converted the a from 1500 km/h to 416.7 m/s
I then used F=ma but I got the result as 333360 N but this answer is incorrect. I'm not quite sure where to go from here and I don't know what the significance of time is. I used it to calculate velocity using v=at and got 875.07 m/s but I don't know how is should use it, if at all.

Thanks for any help anyone can give!
 
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I figured out my mistake!
I thought that 416.7 was acceleration but it is actually velocity.
 

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