Answer:
f = 692 N
Explanation:
given data:
f =800N
a =1.2 m s^{2}
m= 90 kg
from newton's second law
net force ![F_{net} =\sum F = F_1 +F_2 +..... = ma](https://tex.z-dn.net/?f=F_%7Bnet%7D%20%3D%5Csum%20F%20%3D%20F_1%20%2BF_2%20%2B.....%20%3D%20ma)
therefore we have from above equation![F_{net} = F -f = ma](https://tex.z-dn.net/?f=F_%7Bnet%7D%20%3D%20F%20-f%20%3D%20ma)
ma =F - f
putting all value to get force of friction
1.2*90 = 800 - f
f = 692 N
C . Record the time to complete a chemical reaction
Speed = distance / time
S= 40 000m / 5400s
S= 7.41m/s
Solve for "x"
X=force
18/6=x/9
cross multiply
162=6x
x=27
Hope this helps