The area of the circle with radius r is
A = πr²
The rate of change of area with respect to time is
The rate of change of the radius is given as
Therefore
When r = 10 ft, obtain
Answer: - 40π ft²/s (or - 127.5 ft²/s)
Answer:
Explanation:
Magnitude of frictional force = μ mg
μ is either static or kinetic friction.
To start the crate moving , static friction is calculated .
a ) To start crate moving , force required = μ mg where μ is coefficient of static friction .
force required =.517 x 56.6 x 9.8 = 286.76 N .
b ) to slide the crate across the dock at a constant speed , force required
= μ mg where μ is coefficient of kinetic friction , where μ is kinetic friction
= .26 x 56.6 x 9.8 = 144.21 N .
Answer:
Sound waves. Anything that vibrates is producing sound; soundis simply a longitudinal wave passing through a medium via the vibration of particles in themedium. Consider a sound wavetraveling in air
It is correct, the action is paddling, where you move the water backwards, and the reaction is the boat moving forwards.
