Answer:
\(1.4\cdot 10^5 N\)
Explanation:
First of all, we can find the work done as follows:
\(W=Pt\)
where P is the power and t is the time taken. In this problem, \(P=7.0\cdot 10^4 W\) and \(t=40 s\), so the work done is
\(W=Pt=(7.0\cdot 10^4 W)(40 s)=2.8\cdot 10^6 J\)
The work done is equal to the force applied F times the displacement d:
\(W=Fd\)
since we know d=20.0 meters, we can re-arrange the equation to find the force exerted:
\(F=\frac{W}{d}=\frac{2.8\cdot 10^6 J}{20.0 m}=1.4\cdot 10^5 N\)
