Question

Car with mass 940kg is moving at speed 48km/h. How much force do you need to stop it in 15m distance?

Answer 1

first of all find the retardation
\[(48)^2=2*a*D\] and \[a=\frac{ (48)^2 }{ 2*15 }=76.8m/s^2\] now F=m*a
F=940*76.8 N @duck123 you are done

Answer 2

@duck123 Did you understand?

Answer 3

I'm trying to figure out where 2*a*d part is coming from

Answer 4

\[V^2=U^2-2a*D\] V is final velocity which is zero and U is = 48
i have taken -a because it is retardation hope that helps

Answer 5

oh, now i get it. thanks!

Answer 6

:)