The law applied here is Hooke's Law which describes the force exerted by the spring with a given distance. The equation for this is F = kΔx, where F is the force in Newtons, k is the spring constant in N/m while Δx is the displacement in meters.
If you want to find work done by a spring, this can be solved by using differential equations. However, derived equations are already ready for use. The equation is
W = k[{x₂-x₁)² - (x₁-xn)²],
where
xn is the natural length
x₁ is the stretched length
x₂ is also the stretched length when stretched even further than x₁
In this case xn =x₁. So, that means that (x₁-xn) = 0 and (x₂-x₁) = 11 cm or 0.11 m.
Then, substituting the values,
2 J = k (0.11² -0²)
k = 165.29 N/m
Finally, we use the value of k to the Hooke's Law to determine the Force.
F = kΔx = (165.29 N/m)(0.11 m)
F = 18.18 Newtons
A)they can interbreed and produce fertile offsprings
Answer:
his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Explanation:
Let say the speed of the bicycle while he moves towards the city is "v"
now the speed of the round trip must be smaller by 1 mph
so its speed for round trip will be

now we know that total time of the motion is 19 hr
so we will have


so we will have




by solving above equation we have

so his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph