To solve this problem we will apply the principle of buoyancy of Archimedes and the relationship given between density, mass and volume.
By balancing forces, the force of the weight must be counteracted by the buoyancy force, therefore
Here,
m = mass
g =Gravitational energy
The buoyancy force corresponds to that exerted by water, while the mass given there is that of the object, therefore
Remember the expression for which you can determine the relationship between mass, volume and density, in which
In this case the density would be that of the object, replacing
Since the displaced volume of water is 0.429 we will have to
The density of water under normal conditions is 
, so
The density of the object is 
A. Molecular solids tend to have lower melting points than Ionic so it would be Ionic if it weren't for Molecular.
Answer:
Explanation:
Assuming the light takes essentially no time to reach you, the distance at which the lightning occurred can be calculated by multiplying the speed of sound by the time it takes to hear the thunder:
Answer:
magnitude=34.45 m
direction=
Explanation:
Assuming the initial point P1 of this vector is at the origin:
P1=(X1,Y1)=(0,0)
And knowing the other point is P2=(X2,Y2)=(19.5,28.4)
We can find the magnitude and direction of this vector, taking into account a vector has a initial and a final point, with an x-component and a y-component.
For the magnitude we will use the formula to calculate the distance 
between two points:
(1)
(2)
(3)
(4) This is the magnitude of the vector
For the direction, which is the measure of the angle the vector makes with a horizontal line, we will use the following formula:
(5)
(6)
(7)
Finding 
:
(8)
(9) This is the direction of the vector
Answer:
B. 30 m down
Explanation:
In physics we have two types of quantities:
- Scalar quantity: it is a quantity which only has a magnitude (e.g: mass and time are scalar quantities, since they only have a magnitude)
- Vector quantity: it is a quantity which has both a magnitude and a direction (e.g: velocity is a vector quantity, since it has a magnitude (the speed) and a direction)
In this problem, we have:
A. 100 ounces of water --> scalar (this is a volume, which has only a magnitude)
B. 30 m down --> vector (this is a displacement, which has both a magnitude (30 m) and a direction (down)
C. 88 mi/s --> scalar (this is a speed, which has only a magnitude)
D. 45 gallons in a bucket --> scalar (this is a volume, which has only a magnitude)
So, the correct option is B.
