What is the current flowing through the 20-ohm resistor? A. 1 A

A rock with a mass of 540 g in air is found to have an apparent mass of 342 g when submerged in water. (a) What mass of water is

AleksandrR [38]

(a) 198 g

When the rock is submerged into the water, there are two forces acting on the rock:

- its weight, equal to $W=mg$ (m=mass, g=acceleration of gravity), downward

- the buoyant force, equal to $B=m_w g$ ( $m_w$ =mass of water displaced), upward

So the resultant force, which is the apparent weight of the rock (W'), is

$W'=W-B$

which can be rewritten as

$m'g = mg-m_w g$

where m' is the apparent mass of the rock. Using:

m = 540 g

m' = 342 g

we find the mass of water displaced

$m_w = m-m'=540 g-342 g=198 g$

(b) $1.98\cdot 10^{-4} m^3$

If the rock is completely submerged, the volume of the rock corresponds to the volume of water displaced.

The volume of water displaced is given by

$V_w = \frac{m_w}{\rho_w}$

where

$m_w = 198 g = 0.198 kg$ is the mass of the water displaced

$\rho_w = 1000 kg/m^3$ is the density of the water

Substituting,

$V_w = \frac{0.198}{1000}=1.98\cdot 10^{-4} m^3$

And so this is also the volume of the rock.

(c) $2727 kg/m^3$

The average density of the rock is given by

$\rho = \frac{m}{V}$

where

m = 540 g = 0.540 kg is the mass of the rock

$V=1.98\cdot 10^{-4} m^3$ is its volume

Substituting into the equation, we find

$\rho = \frac{0.540 kg}{1.98\cdot 10^{-4}}=2727 kg/m^3$

3 0

4 years ago

vector ????⃗ has a magnitude of 17.9 and its direction is 80∘ counter‑clockwise from the x- axis. what are the x- and y- compone

Reika [66]

We have vector $(17.9*cos80^{0},17.9*sin80^{0})$

Therefore,

x component = 17.9 * cos80 degree = 3.108

y component = 17.9 * sin80 degrees = 17.628

<h3>What is a vector?</h3>

An object with both magnitude and direction is referred to be a vector. A vector can be visualized geometrically as a directed line segment, with an arrow pointing in the direction and a length equal to the magnitude of the vector. The vector points in a direction from its tail to its head.

If the magnitude and direction of two vectors match, they are the same vector. This shows that if we move a vector to a different location without rotating it, the final vector will be the same as the initial vector. The vectors that denote force and velocity are two examples. The direction of force and velocity are both fixed. The size of the vector would represent the force's strength or the velocity's corresponding speed.

To know more about vectors, visit:

brainly.com/question/12937011

#SPJ4

5 0

2 years ago

All moving objects don’t have momentum<br> A. True<br> B. False

mestny [16]

Answer:

No

Explanation:

Some objects gain momentum.

4 0

2 years ago

Read 2 more answers

How many atoms are in 3MgCl2?

Bogdan [553]

Answer:

3MgCl2 has 9 atoms.

Explanation:

The Element Magnesium (Mg) has 3 atoms.

The Element Chloride (Cl) has 6 attoms.

Their fore 6 + 3 is 9 of course. 3MgCl2 has 9 atoms.

BTW: 3MgCl2 is a molecular compound as well as H2O and CO2.

8 0

3 years ago

According to recent research, ice skaters are able to glide smoothly across the ice because _____.

nekit [7.7K]

In the blank should go of friction.

8 0

3 years ago