Answer:
I think the answer is C.
Explanation:
A primary source is a first hand account of an event while a secondary source is a retelling or second hand account meaning as many details will be prevalent.
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
![kx-mg=ma](https://tex.z-dn.net/?f=kx-mg%3Dma)
....(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
![x=2.5\times x_{0}](https://tex.z-dn.net/?f=x%3D2.5%5Ctimes%20x_%7B0%7D)
Here, acceleration is zero
So, ![x=2.5\times\dfrac{mg}{k}](https://tex.z-dn.net/?f=x%3D2.5%5Ctimes%5Cdfrac%7Bmg%7D%7Bk%7D)
We need to calculate the acceleration
Put the value of x in equation (I)
![2.5\times \dfrac{mg}{k}=\dfrac{ma+mg}{k}](https://tex.z-dn.net/?f=2.5%5Ctimes%20%5Cdfrac%7Bmg%7D%7Bk%7D%3D%5Cdfrac%7Bma%2Bmg%7D%7Bk%7D)
![2.5\times\dfrac{mg}{k}=\dfrac{m}{k}(a+g)](https://tex.z-dn.net/?f=2.5%5Ctimes%5Cdfrac%7Bmg%7D%7Bk%7D%3D%5Cdfrac%7Bm%7D%7Bk%7D%28a%2Bg%29)
![a=2.5g-g](https://tex.z-dn.net/?f=a%3D2.5g-g)
![a=1.5g](https://tex.z-dn.net/?f=a%3D1.5g)
Hence, (a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Let's use Newton's 2nd law of motion:
Force = (mass) x (acceleration)
Force = (68 kg) x (1.2 m/s²) = 81.6 newtons .
Answer:
α = 3×10^-5 K^-1
Explanation:
let ΔL be the change in length of the bar of metal, ΔT be the change in temperature, L be the original length of the metal bar and let α be the coefficient of linear expansion.
then, the coefficient of linear expansion is given by:
α = ΔL/(ΔT×L)
= (0.3×10^-3)/(100)(100×10^-3)
= 3×10^-5 K^-1
Therefore, the coefficient of linear expansion is 3×10^-5 K^-1
<span>D. Pressure increases with increasing depth.
This occurs because there is more weight above you to increase the pressure.
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