A person goes for a walk. They go 20 m north, 15 m west , and 10 m south in 45 seconds. a. what was their distance?
b. what was their displacement?
c. what was their speed?
d. what was their velocity?

Which changes of state do the labels represent? a: b: c:

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?

Observations show that interstellar clouds can have almost any shape and