Answer:
A)
B) 
Explanation:
A) Using the Archimedes' force we can find the weight of water displaced:

Where:
: is the weight of the block in the air = 20.1 N
: is the weight of the block in the water = 15.3 N

Now, the mass of the water displaced is:

The volume of the block can be found using the mass of water displaced and the density of the water:

B) The density of the block can be found as follows:

I hope it helps you!
Answer:
Faraday's law
, he direction of the magnetic field changes by 180º, in the polarity inversion processes, induces a voltage.
Explanation:
For this exercise let's use Faraday's law
E = - dФ / dt
Ф = B.A = B A cos θ
where B is the magnetic field, A is the area and θ is the angle between the field line and the normal to the area.
We can see that an electromotive force (voltage) is indexed when there is a variation of the field B, a variation of the area and change of the angle or when there is a combinational of them.
In this case, the magnitude of the field is constant, as the wire is rigid metal, the area is constant, but the direction of the magnetic field changes by 180º, in the polarity inversion processes, for which reason each change induces a voltage.
If a voltage is created in the ring, which has a resistance, a current is also generated in it.
Therefore the answer is If a current is created in the hoop
You would need to use the equation a= (v-u)÷t
You need to substitute in the correct numbers.
a= (10-20)÷1
Your answer is -10m/s^2
Answer:
1. 24375 N/C
2. 2925 V
Explanation:
d = 12 cm = 0.12 m
F = 3.9 x 10^-15 N
q = 1.6 x 10^-19 C
1. The relation between the electric field and the charge is given by
F = q E
So, 

E = 24375 N/C
2. The potential difference and the electric field is related by the given relation.
V = E x d
where, V be the potential difference, E be the electric field strength and d be the distance between the electrodes.
By substituting the values, we get
V = 24375 x 0.12 = 2925 Volt
Answer:
Base-emitter and Base-collector junctions are forward biased