Superman leaps in front of lois lane to save her from a
volleyof bullets. in a 1 minute interval, an automatic weapon
fires160 bullets, each of mass 8.0 g, at450 m/s. the bullets strike
his mightychest, which has an area of 0.71m2. find the
average force exerted on superman's chestif the bullets bounce back
after an elastic, head-on collision. express your anwser in
n.

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?