What did people assume Katherine was when she entered the room?

Answer:

Can be changed from one form to another

Explanation:

According to the law of conservation of energy the total energy of a system remains conserved. It only change state from one form of energy to another.

The total energy is also known as mechanical energy. It is equal to the sum of kinetic energy and the potential energy.

Hence, the correct option is (d) "can be changed from one form to another".

Answer:

D - Can be changed from one form to another

Answer:

Explanation:

Given that,

The current in the light bulb, I = 0.5 A

(a) We know that,

Electric current = charge/time

or

Q = It

Put t = 2 hours = 7200 s

So,

Q = 0.5 × 7200

Q = 3600 C

(b) Charge on one electron, [tex]Q=1.6\times 10^{-19}\ C[/tex]

Let there are n electrons flow through the bulb in 2 hours.

I = Q/t

Since, Q = ne

So,

I = ne/t

[tex]n=\dfrac{I\times t}{e}\\\\n=\dfrac{0.5\times 7200}{1.6\times 10^{-19}}\\\\n=2.25\times 10^{22}[/tex]

Hence, this is the required solution.

Answer:

Sometimes atoms gain or lose electrons. The atom then loses or gains a "negative" charge. These atoms are then called ions. Positive Ion - Occurs when an atom loses an electron negative charge it has more protons than electrons.

Explanation:

:)

Answer:

[tex]R = \frac{V}{A}[/tex]

Explanation:

See attachment for circuit

From the circuit, we have:

[tex]V = Voltage[/tex]

[tex]A = Current[/tex]

[tex]R = Resistance[/tex]

Resistance is calculated as:

[tex]R = \frac{V}{A}[/tex]

The steps are as follows:

Step 1: The student needs first to power on the circuit

Step 2: The student then take readings from both the ammeter (for current) and from the voltmeter (for voltage)

Step 3: Record new readings for current and voltage by adjusting the variable resistor

Step 4: Draw a voltage-current graph

Step 5: : Lastly, calculate the slope of the graph

The slope represents the resistance

Answer:

D. 3 : 1

Explanation:

Let suppose that A and B are particles. From statement we know that [tex]K_{A} = K_{B }[/tex] (same kinetic energy) and [tex]m_{A} = 9\cdot m_{B}[/tex]. Then,

[tex]K_{A} = K_{B}[/tex]

[tex]\frac{1}{2}\cdot m_{A}\cdot v_{A}^{2} = \frac{1}{2}\cdot m_{B}\cdot v_{B}^{2}[/tex]

[tex]m_{A} \cdot v_{A}^{2} = m_{B}\cdot v_{B}^{2}[/tex]

[tex]\frac{v_{B}}{v_{A}} = \sqrt{\frac{m_{A}}{m_{B}} }[/tex]

[tex]\frac{v_{B}}{v_{A}} = 3[/tex]

And the ratio of the momentum of A to the momentum of B is:

[tex]r = \frac{m_{A}\cdot v_{A}}{m_{B}\cdot v_{B}}[/tex]

[tex]r = 9\times \frac{1}{3}[/tex]

[tex]r = 3[/tex]

Hence, the correct answer is D.

Answer:

New force = 2.688 N

Explanation:

Given that,

Two charged particles exert a force of 0.042 N on each other.

Let the initial distance is r. Later the particles are moved such that they are now one-eighth as far apart.

New distance, r' = (r/8)

The force between particles is given by :

[tex]F'=\dfrac{kq_1q_2}{r'^2}\\\\F'=\dfrac{kq_1q_2}{(\dfrac{r}{8})^2}\\\\F'=\dfrac{kq_1q_2}{\dfrac{r^2}{64}}\\\\F'=64\times \dfrac{kq_1q_2}{r^2}\\\\F'=64\times F\\\\F'=64\times 0.042\\\\F'=2.688\ N[/tex]

So, the new force is 2.688 N.

Answer:

Explanation:

Force between two charged conducting sphere

= k x Q₁ x Q₂ / r² ,  k is a constant  Q₁ and Q₂ are charges and   r is distance between them .

= 9 x 10⁹ x 12 x 10⁻⁹ x 18 x 10⁻⁹ / .30²

= 21600 x 10⁻⁹

= 2.16 x 10⁻⁵ N .

b )

After the spheres are joined together , there is redistribution of charge and remaining charge will be equally shared by them .

Charge on each sphere = (12 - 18 ) x 10⁻⁹ / 2

= - 3 x 10⁻⁹ C .

Force = 9 x 10⁹ x 3 x 10⁻⁹ x 3 x 10⁻⁹ / .30²

= 900 x 10⁻⁹ N .

Answer:

solar energy

wind power

geothermal energy

hydraulic power

biomass energy

energy storage

(That's all I know).

Answer:

[tex]20.14\ \text{m}[/tex]

Explanation:

m = Mass of person = 70 kg

k = Spring constant = 100 N/m

h = Total length of the bungee cord = 45 m

The energy balance of the system is

[tex]mgh=\dfrac{1}{2}kx^2\\\Rightarrow x=\sqrt{\dfrac{2mgh}{k}}\\\Rightarrow x=\sqrt{\dfrac{2\times 70\times 9.81\times 45}{100}}\\\Rightarrow x=24.86\ \text{m}[/tex]

Maximum unstretched length would be [tex]h-x=45-24.86=20.14\ \text{m}[/tex].

Answer:

The horizontal distance traveled by the projectile is 373.36 m.

Explanation:

Given;

angle of projection; θ = 30⁰

initial velocity of the projectile, u = 65 m/s

The horizontal distance traveled by the projectile or range of the projectile is calculated as;

[tex]R = \frac{u^2 \times sin(2\theta)}{g} \\\\R = \frac{65^2 \times sin(2\times 30^0)}{9.8}\\\\R = \frac{4225\times sin(60)}{9.8} \\\\R = 373.36 \ m[/tex]

Therefore, the horizontal distance traveled by the projectile is 373.36 m.

Answer:

the momentum is 164500 kg m/s

Explanation:

The computation of the momentum is shown below:

As we know that

Momentum is

= mass × velocity

= 9851.6 kg × 16.7 m/s

= 164522 kg·m/s

= 164500 kg m/s

hence, the momentum is 164500 kg m/s

Light reflects off the fish, except for light of the wavelength the fish

absorbs, making the fish hard to see which is why it must aim for the fish in

a slightly different place.

This is the change in the direction of propagation of a wave that strikes the

boundary between different mediums and in this case, the medium is

water.

The change in direction which occurs during reflection of the light

makes it harder for the Pelican  ro see which is why it must aim for the

fish in a slightly different place.

Read more about Reflection here https://brainly.com/question/26494295

Answer:

Estimate money spent on the appliance( 9 Watt bulb ) on a monthly basis is $0.7776

Explanation:

Given the data in the question;

we are to pick  a small appliance in our home that we use regularly and look up on the internet how much power it operates at;

so lets consider a 9 Watt bulb

Power p = 9 Watt

Household Voltage = 120 v

we know that; Power = Current I × Voltage V

so,

9 = I × 120

I = 9 / 120

I = 0.075 A

Resistance;

R = V / I

R = 120 / 0.075

R = 1600 Ω

Now, Energy consumed in 1 month(30 days) will be;

E = P × Τ

E = ( 9 / 1000kW ) × ( 30 × 24hrs )

E = 0.009 × 720 hrs

E = 6.48 kWh

Now, the cost for one month will be;

Cost = 6.48 × $0.12

Cost = $0.7776

Therefore, estimate money spent on the appliance( 9 Watt bulb ) on a monthly basis is $0.7776

Answer:

Circuit B

Explanation:

To know the correct answer to the question, we shall determine the reading of the ammeter i.e the current in each circuit. This can be obtained as follow:

For circuit A:

Resistance (R) = 5 ohms

Voltage (V) = 1.5 V

Current (I) =?

V = IR

1.5 = I × 5

Divide both side by 5

I = 1.5 / 5

I = 0.3 A

For circuit B:

We'll begin by calculating the total resistance in the circuit. This can be obtained as follow:

Resistance 1 (R₁) = 5 ohms

Resistance 2 (R₂) = 5 ohms

Total resistance (Rₜ) =?

Since they are in parallel connections, the total resistance can be obtained as illustrated below:

Rₜ = R₁ × R₂ / R₁ + R₂

Rₜ = 5 × 5 / 5 + 5

Rₜ = 25 / 10

Rₜ = 2.5 ohms

Finally, we shall determine the current in the circuit.

Resistance (R) = 2.5 ohms

Voltage (V) = 1.5 V

Current =?

V = IR

1.5 = I × 2.5

Divide both side by 2.5

I = 1.5 / 2.5

I = 0.6 A

For circuit C:

We'll begin by calculating the total resistance in the circuit. This can be obtained as follow:

Resistance 1 (R₁) = 5 ohms

Resistance 2 (R₂) = 5 ohms

Total resistance (Rₜ) =?

Since they are in series connections, the total resistance can be obtained as illustrated below:

Rₜ = R₁ + R₂

Rₜ = 5 + 5

Rₜ = 10 ohms

Finally, we shall determine the current in the circuit.

Resistance (R) = 10 ohms

Voltage (V) = 1.5 V

Current =?

V = IR

1.5 = I × 10

Divide both side by 10

I = 1.5 / 10

I = 0.15 A

SUMMARY:

Circuit >>>>>>> Current

A >>>>>>>>>>>> 0.3 A

B >>>>>>>>>>>> 0.6 A

C >>>>>>>>>>>> 0.15 A

from the above calculations, circuit B has the highest ammeter reading.

Answer:

Compared to the first student, the second student did twice as much work as the first student.

Explanation:

The work done by the first student will be equal to the Force exerted by the backpack on the student carrying it multiplied by one mile (Distance).  The work done by the second student will be equal to the Force exerted by the backpack on the student carrying it multiplied by two miles (Distance).

Answer:

sound and happiness are not matter

Explanation:

Answer:

Cytoplasm is the jelly-like fluid that fills in all of the. space between the nucleus and the plasma membrane. All of the organelles within a cell are suspended in this fluid. The main function of the cytoplasm is to support the internal structures of the cell as well as maintaining shape and consistency of the cell.

Answer:

The angular frequency of the ball is 2.173 rad/s.

Explanation:

Given;

mass of the ball, m = 1.8 kg

spring constant, k = 8.5 N/m

maximum displacement of the ball, A = 13 cm = 0.13 m

The angular frequency of the ball is calculated as;

[tex]\omega = \sqrt{\frac{k}{m} } \\\\\omega = \sqrt{\frac{8.5}{1.8}} \\\\\omega = 2.173 \ rad/s[/tex]

Therefore, the angular frequency of the ball is 2.173 rad/s.

Answer:

True

Explanation:

Try watching Demon Slayer on Netflix. It's a new series, and it's very entertaining to watch!! :)

(Brainliest please!)

Answer:

500

p=w/t

w=force *displacement

w=750*20=15000j

p=15000/20=500watt

Explanation:

500

p=w/t

w =force displacement

w=750*20=15000j

p=15000/20=500 watt

Answer:

b

Explanation:

because of bonds and the bowl is used for heating purpose

Answer:

I think b not sure but I hope its right and is that the nwea test??

Answer:

true

Explanation:

Answer:

true

Explanation:

Answer:

26.833 N

Explanation:

The computation of the resaltant of two forces is shown below:

Given that

Force A = 12N

Force B = 24N

Based on the above information  

Resultant R is

[tex]=\sqrt{A^2 + B^2 + 2AB \times cos \theta}\\\\=\sqrt{144 + 576 + 2\times 24\times 12\times cos90^{\circ}}\\\\=\sqrt{144+576+576\times 0}\\\\=\sqrt{720}[/tex]

=26.833 N

Answer:

24ms^-2 (2 sig figs)

Explanation:

F = ma

This means that the sum of all forces (or the net force) acting upon an object is equal to its mass x accelleration.

Its important to convert all parts of this equations in to SI units such that Force (N), Mass (kg) and Accelleration (ms^-2) to make sure that your answer is in the correct units.

F = ma so 5 = 0.21a

a = 5/0.21

a = 23.810 ms^-2 (5 sig figs)

D. A hockey puck sliding across ice

Answer:Radiant to chemical

Explanation: