On a night when the moon rises at 9 pm, what is its phase?

A trip is taken that passes through the following points in order

Inessa05 [86]

Answer:

B) - 5.0 m

Explanation:

B is located on a positive location, 15m from the starting point A. Hence, since E is located a positive distance 10m from A, the difference becomes 10 - 15 = - 5.0 m

5 0

3 years ago

When is your weight is equal to mg?<br>

Vinil7 [7]

Answer:

The weight of an object is defined as the force of gravity on the object and may be calculated as the mass times the acceleration of gravity, w = mg.

6 0

3 years ago

Read 2 more answers

A thin partition divides a thermally insulated vessel into a lower compartment of volume V and an upper compartment of volume 2V

Anni [7]

Answer:

1.89mol

Explanation:

The entropy change during free expansion is express as

$S_{f}-S_{i}=nRln(\frac{V_{F}}{V_{I}})\\$

Where S is the entropy of the system,

n is the amount of mole

R is the gas constant = 8.314 and

V is the volume occupied at the initial and final stage

since the process is n adiabatic free expansion, the entropy of the system is constant. Hence we can re-write the equation as

$S=nRln(\frac{V_{F}}{V_{I}})\\$

where the $V_{i}=v\\$ and $V_{f}=2v+v=3v\\$

$S=17.28J/k\\$ and

$R=8.314\\$

Now if we substitute in values we arrive at

$17.28=(8.314)n*ln(\frac{3v}{v} )\\17.28=(8.314)n*ln(3 )\\17.28=(8.314)n*1.0986\\n=\frac{17.28}{8.314*1.0989}\\n=1.89 mole\\$

6 0

3 years ago

A boat with an anchor on board floats in a swimming pool that is somewhat wider than the boat. Does the pool water level move up

pentagon [3]

Answer:

a) moves down

b) moves down

c) level remains same

Explanation:

Given that the anchor is initially on the floating boat.

a)

In this condition initially the the volume of water $(V_w_i)$ displaced is to balance its weight.

Now,

$W_a=W_w$

$V_a.\rho_a.g=V_w_i.\rho_w.g$

$\frac{\rho_a}{\rho_w} =\frac{V_w_i}{V_a}$

We've, the density of steel $= 7850\ kg.^{-3}$ and the density of water $= 1000\ kg.^{-3}$

$\therefore V_w_i=7.85\times V_a$

When the anchor is dropped into water:

The volume of water displaced be $(V_w_f)$ which will be equal to the volume of anchor since it is immersed into it.

$V_a=V_w_f$

$\therefore V_w_i>V_w_f$ ...................(1)

So the level of water falls when the anchor is dropped into water.

b)

Now, when the anchor is thrown on the ground the water has now less weight to balance so the water level falls down.

c)

When the cork on the from the boat is dropped into the water and it still floats then it must displace same amount of water, hence there should be no change in the water level.

6 0

3 years ago

What is the frequency of a photon that has the same momentum as a neutron moving with a speed of 1.90 × 103 m/s?

Minchanka [31]

The mass of a neutron is:
$m=1.67 \cdot 10^{-27}kg$
Since we know its speed, we can calculate the neutron's momentum:
$p=mv=(1.67 \cdot 10^{-27}kg)(1.90 \cdot 10^3 m/s)=3.17 \cdot 10^{-24} kg m/s$

The problem says the photon has the same momentum of the neutron, p. The photon momentum is given by
$p= \frac{h}{\lambda}$
where h is the Planck constant, and $\lambda$ is the photon wavelength. If we re-arrange the equation and we use the momentum we found before, we can calculate the photon's wavelength:
$\lambda= \frac{h}{p}= \frac{6.6 \cdot 10^{-34}Js}{3.17 \cdot 10^{-24} kg m/s}=2.08 \cdot 10^{-10} m$

And since we know the photon travels at speed of light c, we can now calculate the photon frequency:
$f= \frac{c}{\lambda}= \frac{3 \cdot 10^8 m/s}{2.08 \cdot 10^{-10} m}= 1.44 \cdot 10^{18} Hz$

4 0

3 years ago