Answer:
35.7kJ
Explanation:
we can calculate the amount of heat energy required , using this formula
Q = mcθ
where.
Q = heat energy (Joules, J)
m = mass of a substance (kg)
c = specific heat capacity (units )
θ = change in temperature (Celcius,C or Kelvin K)
Assume Specific heat capacity (c) of water =
mass =0.1 kg
Accuracy is how close you're measurement comes to an accepted or given value. I n many cases you do not know what the accepted value is, so you have nothing to compare your measurement with. The more often a measurement is taken with close precision, or reproducibility, the more likely you are to being close to your unknown accepted value.
There is a great short tutorial video covering accuracy and precision at Sciocity dot com
Density = (mass) divided by (volume)
We know the mass (2.5 g). We need to find the volume.
The penny is a very short cylinder.
The volume of a cylinder is (π · radius² · height).
The penny's radius is 1/2 of its diameter = 9.775 mm.
The 'height' of the cylinder is the penny's thickness = 1.55 mm.
Volume = (π) (9.775 mm)² (1.55 mm)
= (π) (95.55 mm²) (1.55 mm)
= (π) (148.1 mm³)
= 465.3 mm³
We know the volume now. So we could state the density of the penny,
but nobody will understand what we have. Here it is:
mass/volume = 2.5 g / 465.3 mm³ = 0.0054 g/mm³ .
Nobody every talks about density in units of ' gram/(millimeter)³ ' .
It's always ' gram / (centimeter)³ '.
So we have to convert our number for the volume.
(0.0054 g/mm³) x (10 mm / cm)³
= (0.0054 x 1,000) g/cm³
= 5.37 g/cm³ .
This isn't actually very close to what the US mint says for the density
of a penny, but it's in a much better ball park than 0.0054 was.
Answer:
The magnetic field at the center of a circular loop is .
Explanation:
Given that,
Radius = 4.0 cm
Current = 2.0 A
We need to calculate the magnetic field at the center of a circular loop
Using formula of magnetic field
Where, I = current
r = radius
Put the value into the formula
Hence, The magnetic field at the center of a circular loop is .