Answer:
384N
Explanation:
Given parameters:
Mass = 3kg
radius = 0.5m
Speed = 8m/s
Unknown:
Centripetal force = ?
Solution:
The centripetal force is the inward force that keeps a body in motion along a circular path.
It is mathematically expressed as;
F =
m is the mass
v is the speed
r is the radius
Now insert the parameters and solve;
F = = 384N
When the distance between the source and the observer is DEcreasing, the observer sees light that has a<em> shorter wavelength</em> than the light actually had when it left the source.
It doesn't matter how the distance between them is decreasing. The source could be moving toward the observer, the observer could be moving toward the source, or they could both be moving in a way that makes the separation between them decrease as time goes on. The result is the same.
(When this is used in Astronomy and Astrophysics, the big trick is: How does the observer know what the wavelength actually WAS when the light left the source ?)
Average speed = total distance / total time
total distance = 40 + 20 = 60km
total time taken = 10 + 5 = 15 minutes
Average speed = 60/15 = 4km/min