Answer:
C. 21 Joules
Explanation:
We apply the formula to calculate the potential energy (Ep):
Ep=m*g*h
Where:
Ep : potential energy in Joules (J)
m :mass in kilograms (kg)
g acceleration due to gravity (m/s²)
h: height in meters (m)
Calculation of the height (h)
Ep = m*g*h
7 = (1.5 )*(9.8) *(h
)
7 = (14.7) (h
)
h = 7 / (14.7)
h= 0.476 m
Gravitational potential energy of the second object
Ep = m*g*h
Ep = (4.5 )*(9.8) *(0.476
)
Ep = (4.5 )*(9.8) *(0.476
)
Ep = 21 J
Did you try googling it lol thats what i do if its a problem like that. sometimes there are websites that answer it you just have to look really hard
There would be a symbol on names of the elements that would say which state it would usually be in.
there are more metals in the periodic table of elements (currently) if that's what the second question is asking about
Answer:

Explanation:
The cross section area of the cable is

Let g = 9.81m/s2. The stress acting on the cable when mass is added is

The strain when the cable is stretched from 4.76 to 5.43 m is

So the young modulus of the cable is

Answer:
Δy=0.431m
Explanation:
Diffraction grating with split space d,to find the fringe position ym,we must to find the angle from
dSinα=mλ
A grating with N slits or lines per mm has slit spacing of
d=1/N
d=(1/600mm)
d=1.67×10⁻³mm
For 400nm wavelength:
α=Sin⁻¹(mλ/d)

And the position of first order lowest wavelength fringe on the screen is:

For 700nm wavelength:
α=Sin⁻¹(mλ/d)

And the position of first order highest wavelength fringe on the screen is:

The difference between the first order lowest and highest wavelength fringe is
Δy=(0.925595 - 0.49445)m
Δy=0.431m