Answer:
(a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Explanation:
Given that,
Acceleration = a
mass = m
spring constant = k
(a). We need to calculate the spring compressed
Using balance equation

....(I)
The spring compressed is
.
(b). If the compression is 2.5 times larger than it is when the mass sits in a still elevator,
The compression is given by

Here, acceleration is zero
So, 
We need to calculate the acceleration
Put the value of x in equation (I)




Hence, (a). The spring compressed is
.
(b). The acceleration is 1.5 g.
By looking at how wiggily the bar is lol
Answer:

Explanation:
We are given that
Gravitational force=
r=0,U(0)=0
We know that
Gravitational potential energy=


Substitute r=0 ,U(0)=0


Substitute the value

From the law of Galileo Galilei :v²=v₀²+2ad we take the speed
v²=0+2*4.90*200=1960=>v=√1960=44.27 m/s
Answer: (1) The correct answer is A.
(2) The correct answer is D.
Explanation:
(1)
Reflection is the sending back of light from the surface without absorbing it. In the reflection phenomenon, the wave does not continue moving forward.
Diffraction is the bending of the light around the obstacle. In the diffraction phenomenon, the wave travels forward after striking around the obstacle.
Therefore, the correct answer is A.
(2)
Amplitude is the maximum displacement in the medium from the rest position.
The amount of energy is related to the amplitude. Amplitude is related to the amount of energy carried by the wave. Low energy wave is characterized by a low amplitude. High energy wave is characterized by a high amplitude.
Therefore, the correct option is D.