a)120 N*s
b)300 Newtons
Explanation
Impulse is calculated as force multiplied by time. So the largest impulses are created by large forces optimised for the time it takes to perform a skill.
[tex]\text{ Impulse= F}_{average}\cdot\Delta t[/tex]so
Step 1
Let
[tex]\begin{gathered} F=600\text{ N} \\ \Delta t=t=0.2s \end{gathered}[/tex]Step 2
replace in the expression and calculate
[tex]\begin{gathered} \text{ Impulse= F}_{average}\cdot\Delta t \\ I=600\text{ N}\cdot0.2\text{ s} \\ I=120\text{ N}\cdot s \end{gathered}[/tex]therefore, for a)
the impulse is 120 N*s
Step 3
b)If the impulse stayed the same but the time of contact was doubled, how much force would be exerted on them?
then, let
[tex]\begin{gathered} I\text{ =(same)=120 N}\cdot s \\ t=2t_1=2\cdot0.2s=0.4s_{} \\ so\text{ , replace and solve for f} \end{gathered}[/tex][tex]\begin{gathered} \text{ Impulse= F}_{average}\cdot\Delta t \\ 120\text{ N}\cdot s=F\cdot0.4s \\ \text{divide both sides by 0.4 s} \\ \frac{120\text{ N}\cdot s}{0.4\text{ s}}=\frac{F\cdot0.4s}{0.4s} \\ 300\text{ N=F} \end{gathered}[/tex]hence, the exerted force is
300 Newtons
I hope this helps you