1). Take a sample of the substance. The sample should be the largest
possible that will allow it to be be easily handled and the following steps
to be performed with it.
(The density doesn't depend on the size of the sample, and every sample
of the same substance has the same density. But using a larger sample
can improve the accuracy of the measurements you make, and therefore
improve the accuracy of the density you derive for the substance.)
2). Ask or measure the mass of the sample.
3). Ask or measure the volume of the sample.
4). Divide the mass by the volume. Their quotient is the density
of the substance.
Answer:
B
Explanation:
A solenoid is the wraps of conducting wire wrapped around the metal core .
Answer:
Part a)

Part b)

Explanation:
Part a)
Initial value of magnetic flux is given as


so we have

Final flux through the loop is given as

now EMF is given as



Part b)
If magnetic field is constant while Area is changing
So EMF is given as



Answer:
the magnitude of the magnetic field is 0.45 mT
Explanation:
Knowing the formula
B = 
i = 3A i' = 0A
B = 
B = 0.45 mT
The ball needs to accelerate with a magnitude <em>a</em> (pointed towards the center of the circle) of
<em>a</em> = (5.0 m/s)² / (2.0 m) = 12.5 m/s²
Then the required tension <em>F</em> in the string would need to be
<em>F</em> = (2 kg) (12.5 m/s²) = 25 N