weightlessness is the complete or near complete absense of the sensation of weight.
when in freefall,the only force acting upon your body is the force of gravity a noun contact force.since the gravity cannot be felt without any other opposing forces,you would have no sensation of it.you would feel weightless when in a state of freefall.
The Doppler effect occurs when a source of sound or light
moves either toward or away from the observer.
Answer:
A)
B)
Explanation:
Given that
Force = F
Increase in Kinetic energy = 
we know that
Work done by all the forces =change in the kinetic energy
a)
Lets distance = d
We know work done by force F
W= F .d
F.d=ΔKE
b)
If the force become twice
F' = 2 F
F'.d=ΔKE'
2 F .d = ΔKE' ( F.d =Δ KE)
2ΔKE = ΔKE'
Therefore the final kinetic energy will become the twice if the force become twice.
Answer:
160N/m
Explanation:
According to Hooke's law which states that the extension of an elastic material is directly proportional to the applied force provided that the elastic limit is not exceeded. Mathematically,
F = ke where
F is the applied force
k is the spring constant
e is the extension
From the formula k = F/e
Since the body accelerates when the block is released, F = ma according to Newton's second law of motion.
The spring constant k = ma/e where
m is the mass of the block = 0.4kg
a is the acceleration = 8.0m/s²
e is the extension of the spring = 2.0cm = 0.02m
K = 0.4×8/0.02
K = 3.2/0.02
K = 160N/m
The spring constant of the spring is therefore 160N/m
