Physics 161 Forces Homework: Calc Net Force of 340 kg Rocket Sled

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To calculate the net force required to accelerate a 340 kg rocket sled from rest to 1900 km/h in 2.6 seconds, the acceleration must first be determined. The correct conversion of 1900 km/h to meters per second is essential, approximating to about 500 m/s. This results in an acceleration of approximately 200 m/s². Using Newton's second law, F = ma, the net force is calculated to be around 68,000 N. The discussion emphasizes the importance of unit conversion and proper application of formulas in solving physics problems.
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Homework Statement



1. A 340 kg rocket sled can be accelerated at a constant rate from rest to 1900 km/h in 2.6 s. What is the magnitude of the required net force?


Homework Equations





The Attempt at a Solution


1. So I tried calculating the acceleration and multiplying it by the mass. For the acceleration I tried dividing 1900km/h by 2.6s and multiplying it by the mass however that did not work.
 
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Kawasaki268F said:

Homework Statement



1. A 340 kg rocket sled can be accelerated at a constant rate from rest to 1900 km/h in 2.6 s. What is the magnitude of the required net force?


Homework Equations





The Attempt at a Solution


1. So I tried calculating the acceleration and multiplying it by the mass. For the acceleration I tried dividing 1900km/h by 2.6s and multiplying it by the mass however that did not work.

This may sound silly, but you did convert the 1900 km/h to m/s didn't you?
 
Yes sorry I did do that, forgot to mention that above
 
C268 said:
Yes sorry I did do that, forgot to mention that above

Ok approximating

1900km/h is a little over 500 m/s

A little over 500 in 2.6 must be about 500 in 2.5 seconds so acceleration is around 200 ms-2

F = ma says 200 * 340 so approx 68 000 N

What answer did you get?
 
PeterO said:
Ok approximating

1900km/h is a little over 500 m/s

A little over 500 in 2.6 must be about 500 in 2.5 seconds so acceleration is around 200 ms-2

F = ma says 200 * 340 so approx 68 000 N

What answer did you get?

Sweet thanks! I just forgot about the squared part on 200m/s
 
Kawasaki268F said:
Sweet thanks! I just forgot about the squared part on 200m/s

Are you saying the only error you had was in the units of an answer? because none of the numbers in this problem are squared?
 
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