Answer:
Resistance is a measure of the opposition to current flow in an electrical circuit.All materials resist current flow to some degree. They fall into one of two broad categories: Conductors: Materials that offer very little resistance where electrons can move easily.
a current of 12 A flows through a fan for 30 minutes.How many charge flows through then fan during this time?
Answer:
Q=21600C
Explanation:
Q=It.
Data
I=12A
t=30min
convert time from minutes to second
t=60*30
=1800s
Q=?
Q=It
=(12A)*(1800s)
Q=21600C
A person skateboards at 3.25 m/s for 55.0 s. How far did he travel?
A parallel network consist of three resistors 4 ohm, 8 ohm and 16 ohm .If the current in 8 ohm resistor is 3 A then what are the currents in other resistors
Answer:
If the resistors are in parallel they must all experience the same voltage drop.
R * I = V
8 * 3 = 24 V (if i is 3 amps)
24V / 4 ohm = 6 amps
24V / 16 ohm = 1.5 amps
A ship anchored at sea is rocked by waves that have crests Lim apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Question: A ship anchored at sea is rocked by waves that have crests 100 m apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Answer:
0.7 Hz
Explanation:
Applying,
v = λf............... Equation 1
Where v = velocity of the wave, f = frequency fo the wave, λ = wavelength of the wave
make f the subject of the equation
f = v/λ................. Equation 2
From the question,
Given: v = 70 m/s, λ = 100 m ( distance between successive crest)
Substitute these values into equation 2
f = 70/100
f = 0.7 Hz
Hence the frequency at which the wave reach the ship is 0.7 Hz
18. Magnesium is a silvery-grey metal. When heated in air it reacts with oxygen burning with a bright flame to form a white powder called magnesium oxide. From the paragraph identity a) TWO elements (2 marks)
Answer:Magnesium and OXYGENNNN
Explanation:
Magnesium Oxide is still technically Magnesium
A meter 0.0525 m from a wire measures a magnetic field of 7.14 x 10-6 T. How much current flows through the wire?
Answer:
[tex]I=1.9A[/tex]
Explanation:
From the question we are told that:
Meter distance [tex]d=0.0525[/tex]
Magnetic field [tex]B=7.14*19^{-6}T[/tex]
Generally the equation for Magnetic field B is mathematically given by
[tex]B =\frac{\mu *I }{2* \pi r}[/tex]
[tex]7.14*19^{-6}T =\frac{ 1.26 *10^{-6} *I }{2* 3.142*0.0525}[/tex]
Where
Constant[tex]\mu=1.26 *10^{-6}[/tex]
[tex]I=1.9A[/tex]
Therefore
The Current through the wire is
[tex]I=1.9A[/tex]
Answer: 1.87
Explanation:
acellus
What is the mass of a cart that has an acceleration of 10m/s^2 when a net force of 2000 N is applied to it?
Please I need the answer...
Answer:
200kg is the answer to the question
At 10-10 s during the evolution of the universe,______
formed, which are elementary particles that make
up protons and neutrons
What’s in the blank ?
Answer: Quarks
Explanation:
Quarks are the elementary particles that make up protons and neutrons. If you want to be more specific, there's six types, but overall, it's just quarks.
Hello all, can you please answer this? I am struggling with this. I need this by tommorow. Question is below:
Light waves of frequency 6 x 10^14 Hz have a wavlength of 3.75 x 10^-7 m in water. What is their speed in water?
[tex]c_{water} = 2.25\times 10^{8}m/s[/tex]
Explanation:
The speed of light in any medium is given by
[tex]c = \lambda \nu[/tex]
where [tex]\lambda[/tex] is the wavelength and [tex]\nu[/tex] is the frequency. In water,
[tex]c_{water} = \lambda_{water} \nu[/tex]
[tex]\:\:\:\:\:\:\:\:= (3.75\times 10^{-7}\:m)(6\times 10^{14})\:Hz[/tex]
[tex]\:\:\:\:\:\:\:\:= 2.25\times 10^{8}\:m/s[/tex]
What effect does the distance between Earth and the Sun have on Earth’s seasons?
Answer:
So actually, it is not so much the distance at a particular time that affects the seasons. It is a common misconception. It is in-fact the earths tilt. When we rotate around the sun, due to our tilt, the North and South of earth have different seasons. This is because when light is shining on to earth, because of Earths tilt, on one half the light shines more directly and on the other it scatters thus the different temperatures, causing season. Hope this helps.
Amigos necesito que me ayuden a resolver esta gráfica :').
Answer:
ANO BA TO?(;-;)
Explanation:
miss the rage??
An elevator of 3 × 10^4N is raised to a height of 100m in 20s . The work done by electric motor is equivalent to ?
Answer:
we neglect the time data
A bus travels with a constant speed of 48km/h. How long will it take to travel 60km?
Answer:
It will take 1 hr and 15 mins.
Explanation:
Let's look at the speed equation:
s=d/t
We want to find the time, and we have the speed and the distance, so we rearrange the equation. t will be on one side and s and d will be on the other side.
t=d/s
t=60km/(48km/h)
t=1.25h
an object that is 15 cm tall is placed 44 cm in front of a diverging lens. A virtual image appears -14cm in front of the lens. determine the focal length of the lens .
SHOW YOUR WORK.
A) 0.09cm
B)-20.53cm
C)10.6cm
D)-0.04cm
Answer:
The correct option is (b).
Explanation:
Given that,
The height of the object, h = 15 cm
Object distance, u = -44 cm
Image distance, v = -14 cm
We need to find the focal length of the lens. Using the lens formula.
[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}\\\\\dfrac{1}{f}=\dfrac{1}{(-14)}-\dfrac{1}{(-44)}\\\\f=-20.53\ cm[/tex]
So, the focal length of the lens (-20.53 cm).
A 90kg football receiver named Reggie is running at 6.7m/s to catch a pass. A defensive back (103kg) named
Julio is waiting in position to hit him (standing still). They fall to the ground together after the tackle. How fast
are they going after the collision?
Answer: reciever is going to be going the momentum which is 90 times 6.7, so defensive back who is 103 KG and standing still therefore has no momentum, so the collision is 6.7 m/s against the defense
Explanation:
zero momentum
newton's 1st law of motion, when something is acted upon by an unbalanced force.
Which instrument changes kinetic energy into electrical energy?
electric motor
hair drier
electric bell
dynamo
Answer:
Dynamo
Explanation:
Dynamo started to rotate which is known as kinetic energy.When dynamo is in running it produces electricity.dynamo specially used for generating electricity.
A long straight wire is parallel to one edge and is in the plane of a single-turn rectangular loop as shown. If the loop is moving in the plane shown so that the distance x changes at a constant rate of 20 cm/s, what is the magnitude of the emf induced in the loop at the instant x = 5.0 cm? Let / = 50 A, a = 50 cm, b = 6.0 cm.
Answer:
The magnitude of the emf induced in the loop is 2.4 × 10⁻⁵ V
Explanation:
The magnitude of the induced emf of a loop moving relative to a wire is given as follows;
The given parameters are;
I = 50 A, a = 50 cm, and b = 6.0 cm
The constant rate of change of x, v = 20 cm/s
Motional emf formula
The magnetic field due to the straight wire, B = μ₀·i/(2·π·x)
The flux given by the rectangular loop, Ф = BA = μ₀·i/(2·π·x) × a × b
Therefore, we get;
[tex]e = \dfrac{-d\phi}{dt} = \dfrac{-\mu_0 \cdot i \cdot a\cdot b}{2 \cdot \pi} \times \dfrac{d}{dt} \left (\dfrac{1}{x} \right ) = \dfrac{-\mu_0 \cdot i \cdot a\cdot b}{2 \cdot \pi} \times \left (\dfrac{1}{x^2} \right ) \dfrac{dx}{dt}[/tex]
[tex]\because \dfrac{dx}{dt} = v[/tex]
Therefore;
[tex]e = \dfrac{-\mu_0 \cdot i \cdot a\cdot b}{2 \cdot \pi} \times \left (\dfrac{1}{x^2} \right ) \dfrac{dx}{dt} = \dfrac{-\mu_0 \cdot i \cdot a\cdot b}{2 \cdot \pi} \times \left (\dfrac{1}{x^2} \right ) \times v \left(\because \dfrac{dx}{dt} = v \right)[/tex]
μ₀ = 4·π × 10⁻⁷ H/m
We get;
[tex]e = \dfrac{4\cdot \pi \times 10^{-7} \, H/m\times50 \, A \times 0.5 \, m\times 0.06 \, m}{2 \cdot \pi} \times \left (\dfrac{1}{(0.05 \, m)^2} \right ) \times 0.2 \ m/s = 2.4 \times 10^{-5} \, V[/tex]
The induced emf, e = 2.4 × 10⁻⁵ V
A 1000 kg car accelerates from rest at a rate of 10 m/s² for 3 seconds. A) what is the final velocity of the car?
Answer:
Explanation:
We don't need the mass of the car in the equation to solve for final velocity, since the values given for the acceleration and the time it took to accelerate to that velocity are given. The equation we need is the one for acceleration, which is
[tex]a=\frac{v_f-v_0}{t}[/tex] We are solving for final velocity, we know the initial velocity is 0 (starting from rest), and the time to complete this acceleration (10 m/s/s) is 3 seconds:
[tex]10=\frac{v_f-0}{3}[/tex] which is the same thing as saying
[tex]10=\frac{v}{3}[/tex] so
v = 30 m/s
Two uniform bars of the same dimensions are constructed from the same material. One bar has five evenly spaced holes through it and the second bar has only two holes. In these cases, the bars are slid over vertical pegs and rest on a horizontal surface, where friction between the bar and the surface is negligible. The two bars are each pulled by
horizontal forces of equal magnitude F from their right end as shown above. The bars' resulting angular accelerations are recorded.
Is the magnitude of the initial angular acceleration of the bar in case 1 larger than, smaller than or equal to the magnitude of the initial angular acceleration of the bar in Case 2? Explain your reasoning.
Solution :
The angular acceleration, [tex]$\alpha$[/tex] is obtained from the equation of the [tex]$\text{Newton's second law}$[/tex] of rotational motion,
Thus,
[tex]$\tau = F \times d$[/tex]
or [tex]$\tau = I \times \alpha$[/tex]
where [tex]$\tau$[/tex] is torque, F is force, d is moment arm distance, I is the moment of inertia
Thus, [tex]$\alpha=\frac{(F\times d)}{I}$[/tex]
Now if the force and the moment arm distance are constant, then the [tex]\text{angular acceleration is inversely proportional to the moment of inertia.}[/tex]
That is when, F = d = constant, then [tex]$\alpha \propto \frac{1}{I}$[/tex] .
Thus, moment of inertia, I is proportional to mass of the bar.
The mass is less for the bar in case (1) in comparison with that with the bar in case (2) due to the holes that is made in the bar.
Therefore, the bar in case (1), has less moment of inertia and a greater angular acceleration.
2. In a chemical reaction
a) The atoms of the reactants always stay together to form the products
b) The atoms of the reactants unbond, rearrange, and then rebond to form the products
c) New atoms are formed which combine to make the products
d) Some atoms disappear while others multiply to form the products
Answer:
what I think in my opinion is B
The Statue of Liberty is made of Copper that has turned on Says has WAGNE Bongo Wantse
said about this change?
The change is a physical change because the owner in the same is still there,
The change is a physical change beave a new chemical is was on the outside of the sale,
The change is not a physical change beans the plos at the stanje na dana),
The change is nga physical change because a new chemical istmes on the outside of the stalye
Complete Question:
The Statue of Liberty is made of copper that has turned green because it has undergone a change. What can be said about this change?
Group of answer choices.
A. The change is a physical change because the copper in the statue is still there.
B. The change is a physical change because a new chemical is formed on the outside of the statue.
C. The change is not a physical change because the color of the statue has changed.
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Answer:
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Explanation:
A physical change can be defined as a type of change that only affects the physical form of a chemical substance (matter) without having any effect on its chemical properties. Thus, a physical change would only affect the physical appearance and properties of a chemical substance (matter) but not its chemical properties.
This ultimately implies that, a physical change result in a change of matter from one form or phase (liquid, solid or gas) to another without a corresponding change in chemical composition.
Additionally, a physical change is a type of change that involves an increase or decrease in the volume of a physical object (object). Also, this change can be reversed to the original state under certain conditions.
Since the Statue of Liberty which is made of copper turned green, the change is not a physical change because a new chemical is formed on the outside of the statue.
the force acting normally per unit area on the surface of the body is known as
ssooeorkgogogoogkrorooror
Answer:
ssooeorkgogogoogkrorooror
Explanation:
the length of second hand of clock is 14cm, an ant sits on the top of second hand. find the following
i) speed of ant
ii) distance covered by ant in 150 seconds
iii) displacement in 150 seconds
Answer:
The answer is below
Explanation:
i) Since the length of the second clock (radius) is 14 cm = 0.14 m, the distance covered by the second hand in one revelution is:
Distance covered = 2πr = 2π(0.14) = 0.88 m
The time taking to complete one revolution = 60 seconds, hence;
Speed = distance covered in one revolution / time take o complete a revolution
Speed = 0.88 m / 60 s = 0.0147 m/s
ii) Distance covered in 150 s = speed * 150 s = 0.0147 * 150 = 2.2 m
iii) Displacement in 150 seconds = distance from initial position to final position
At 150 s, the hand has covered 2 revolutions and moved 30 s. Hence:
Displacement in 150 seconds = speed * 30 s = 0.0147 * 30 = 0.44 m
A circuit diagram with a power source labeled 12 V is connected to 3 resistors in series. The resistors are labeled 1.0 Ohms, 2.0 Ohms, and 3 Ohms. Calculate the equivalent resistance in the circuit shown.
0.55 Ω
1.8 Ω
2.0 Ω
Its A "0.55" I guessed and got it right
Answer:
there it is fella u were right with ur answer
would volcanic activity have a noticable impact on climate over the next 50 years?
Answer:
yes
Explanation:
The gases and dust particles thrown into the atmosphere during volcanic eruptions have influences on climate. ... Volcanoes have also caused global warming over millions of years during times in Earth's history when extreme amounts of volcanism occurred, releasing greenhouse gases into the atmosphere.
The specitic heat capacity of oxygen is 918 J/kg °C. The specific heat capacity of water is 4181 J/kg °C. Which substance will require more energy to raise its temperature by 1°C?
Answer:
Water
Explanation:
Given the specific heat of oxygen is 918J/kg °C and the specific heat of water is 4181 J/kg °C.
Consider 1Kg mass of each substance.
Now 1 Kg of oxygen needs 918 J of energy to raise its temperature by 1 °C
Also, 1 Kg of water needs 4181 J of energy to raise its temperature by 1 °C.
Clearly water requires more energy when compared to oxygen.
Basically, specific heat capacity is the amount of energy required to raise the temperature of a 1 kg body by 1 °C.
A cubic box has a 0.6 cubic decimetre side. Find the mass of air in the box in gram. (1 Liter of air has a mass of 1.3 g).
Answer:
The mass of air in the box is 0.78 grams.
Explanation:
A litre equals a cubic decimetre. By definition of density ([tex]\rho[/tex]), in grams per litre, we calculate the mass of air inside the cube ([tex]m[/tex]), in grams:
[tex]m = \rho \cdot V[/tex] (1)
Where [tex]V[/tex] is the volume occupied by air within the cube, in litres.
If we know that [tex]V = 0.6\,L[/tex] and [tex]\rho = 1.3\,\frac{g}{L}[/tex], then the mass of air is:
[tex]m = \left(1.3\,\frac{g}{L} \right)\cdot (0.6\,L)[/tex]
[tex]m = 0.78\,g[/tex]
The mass of air in the box is 0.78 grams.
HELP
Question 1 of 25
A boy throws a ball straight up with a speed of 21.5 m/s. The ball has a mass
of 0.19 kg. How much gravitational potential energy will the ball have at the
top of its flight? (Assume there is no air resistance.)
O A. 48.5J
B. 41.2J
O C. 43.9 J
O D. 37.5J
Answer:
Explanation:
Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.
The equation for Potential Energy is PE = mgh. We have everything but the height of the ball. We have to solve for that using a one-dimensional motion equation:
v² = v₀² + 2aΔx, where Δx is our displacement (the height we need for PE). Filling in and keeping in mind that at the max height of parabolic travel, the final velocity of the object is 0:
0 = (21.5)² + 2(-9.8)Δx and
0 = 462.25 - 19.6Δx and
-462.25 = -19.6Δx so
Δx = 23.58 m. Using this as the h in our PE equation:
PE = .19(9.8)(23.58) so
PE = 43.9 J, choice C.
Show your work please
Answer:
[tex] V = U + at[/tex]
Explanation:
Given the following data;
Initial velocity = 0 (since the stone is starting from rest).
Final velocity = 32 m/s
Acceleration = g = 10 m/s²
Time = 3.2 seconds
To show that the speed of the stone when it hits the ground is 32 m/s, we would use the first equation of motion;
[tex] V = U + at[/tex]
Where;
V is the final velocity. U is the initial velocity. a is the acceleration. t is the time measured in seconds.Substituting into the formula, we have;
[tex] 32 = 0 + 10*3.2[/tex]
[tex] 32 = 0 + 32 [/tex]
[tex] 32 = 32 [/tex]
Proven: 32 m/s = 32 m/s