POSSIBLE 1. Which of the following are examples of a physical reactions: (1) ice melting, (2) pencil breaking, (3) iron rusting, (4) wood burning? a. 1.4 b. 3,4 c. 2.3 d. 1,2
Answer:
D) 1 & 2
Explanation:
Ice melting can be refrozen and although the pencil breaks, it doesn't change the chemical formula of the pencil
the light beam falls on the surface of the mirror at an angle of 50 ° and is reflected. What is the magnitude of the reflection angle of that fiber?
Answer:
The Magnitude of the angle of reflection equals that of Incidence from the Law of reflection
So its 50°.
Explanation:
is a
The wire in a simple circuit
which forms an
unbroken pathway, allowing the
electric charges to flow.
A. switch
B. insulator
C. resistor
D. conductor
Answer:
I believe the answer is D: Conductor.
A circuit has an overall resistance of 40 ohms and a current of 200mA.
What is the potential difference in this circuit?
Answer:
Hey!
_________________
Voltage (V) = 0.8V
Current (I) = 200 mA = 200/10^3 = 2/10
Resistance = ?
Resistance = Voltage / Current
Voltage = Current × Resistance
0.8 = 2/10 × Resistance
0.8×10/2 = Resistance
8/2 = Resistance
Resistance = 4 ohm
_________________
Hope it helps...!!!
Explanation:
Explain how interactions can both benefical and harmful to the organisms in an community
the spring constant for each of these springs 100 000 N m-1. Calculate the distance that each of these rear springs is compressed by this vehicle as shown in the diagram above
Answer:
sorry
Explanation:
What is the intensity of sound produced by an elephant's call if it has a power of 0.45 W and you are standing 32.5 m away from the lumbering beast
Answer:
I = 1.36 x 10⁻⁴ W/m²
Explanation:
The intensity of the sound produced by the Elephant can be calculated by using the following formula:
[tex]I = \frac{P}{A} \\\\[/tex]
where,
I = Intensity of sound = ?
P = power of sound = 0.45 W
A = area = πr² = π(32.5 m)² = 3318.3 m²
Therefore,
[tex]I = \frac{0.45\ W}{3318.3\ m^2} \\\\[/tex]
I = 1.36 x 10⁻⁴ W/m²
A bowling ball moving with a velocity of 5V to the right collides elastically with a beach ball moving at a velocity 2V to the left. The bowling ball barely slows down. What is the approximate velocity of the beach ball after the collision?
Answer:
[tex]v'_2=3V[/tex]
Explanation:
From the question we are told that:
Bowling ball Speed [tex]v_1=5 m/s[/tex]
Beach ball Speed [tex]v_2=2 m/s[/tex]
Let The Mass be equal i.e
[tex]M_1=M_2[/tex]
Therefore
Generally the equation for Velocity of beach ball after collision [tex]v'_2[/tex] is mathematically given by
Since Velocity is Vector Quantity
Therefore
[tex]v'_2=v_1-v_2[/tex]
[tex]v'_2=5-2[/tex]
[tex]v'_2=3V[/tex]
What is globalization?
Answer:the process by which businesses or other organizations develop international influence or start operating on an international scale.
Explanation:
9. Bryce drove his car 10 km from his house to Belle Plaine. It took him 8 minutes. He got stopped at a long
traffic light on the return home and so he took 2 minutes longer on the return trip. What was Bryce's average
speed in km per minute? (3 pt)
Answer:
2 km/minuteExplanation:
Here, we are asked to calculate the average speed in km/minute.
As we know that,
Average speed = Total distance ÷ Total time takenHere,
→ Total distance = 10 km + 10 km
Because, he first drove 10 km from his house to Belle Plaine and then he again came back to his house.→ Total distance = 20 km
→ Total time = 8 minutes + 2 minutes
→ Total time = 10 minutes
Substitute the values in the formula of average speed,
→ Average speed = Total distance ÷ Total time taken
→ Average speed = 20km ÷ 10 minutes
→ Average speed = 2 km per minutePlease, I need to finish my homework.
An object is to the left of a convex mirror. Describe the two rays needed to indicate the location and height of the image. Additionally, state what side of the mirror the image is on and whether it is real or virtual.
Answer:
mark me as the brainly plss
how can a sound of a different note be produced in a guitar without changing the length of wire?
Answer:
how tightly strung the wire is
-- Make the string tighter or looser.
-- Keep the same length, but make the string thicker or thinner.
-- Touch the string at a point exactly 1/2, 1/3, 1/4, or 1/5 of its length from one end.
There are 2 ways of collecting the sun’s energy. What are they? Give an example of each.
A wire lying along a y axis form y=0 to y=0.25 m carries a current of 2.0 mA in the negative direction of the axis. the wire fully lies in a magnetic field given by (0.3y)i + (0.4y)j Tesla. what is The magnetic force on the wire
A: (0.15i+0.2j) N
B: (0.0015i+0.002j) N
C: (-6.25E-5 k) N
D:(6.25E-5 k) N
E: None of the above
Answer:
E: None of the above
Explanation:
Since the force on the wire F = ∫idL × B where i = current in wire = 2.0 mA = 2.0 × 10⁻³ A, dL = vector length of wire = dyj and we integrate from y₁ = 0 m and y₂ = 0.25 m, and B = magnetic field = (0.3y)i + (0.4y)j
So, F = ∫idL × B
and we integrate from y₁ = 0 m and y₂ = 0.25 m
F = 2.0 × 10⁻³ A∫₀⁰°²⁵[dyj m × (0.3y)i + (0.4y)j]
F = 2.0 × 10⁻³ A∫₀⁰°²⁵[dyj m × (0.3y)i + dyj m × (0.4y)j]
F = 2.0 × 10⁻³ A∫₀⁰°²⁵[(0.3y) × dy(j × i) + 0.25 × (0.4y)(j × j)]
F = 2.0 × 10⁻³ A∫₀⁰°²°⁵[(0.3ydy(-k) + 0.1y)(0)]
F = 2.0 × 10⁻³ A∫₀⁰°²⁵(-0.3ydy)k
F = 2.0 × 10⁻³ A[-0.3y²/2]₀⁰°²⁵k
F = -2.0 × 10⁻³ A[0.3(0.25)²/2 - 0.3(0)²/2]k
F = -2.0 × 10⁻³ A[0.3(0.0625)/2 - 0]k
F = -2.0 × 10⁻³ A[0.3(0.0625)/2]k
F = -1 × 10⁻³[0.01875]k N
F = -[0.01875 × 10⁻³]k N
F = -[1.875 × 10⁻⁵]k N
Since the answer is not contained in the options, the answer is E.
Suppose your class invites a person to give a speech. When you test out the sound system in the gym you find there are so many echoes the speaker cannot be understood. What needs to be done to fix this problem?
Answer:
You either need to lower the volume so the sounds intensity is lessened. Or you can pad the walls to absorb the sound rather than defect.
Explanation:
Sound intensity allows it to be heard further, but in an enclosed room it will start returning. Sound will deflect off of hard objects do to its interactions with solids. A softer and foamy material can dampen it.
The bumper cars crash into each other and stop. Explain why both bumper cars stop after the crash. [4marks]
Answer:
The collision is inelastic
Explanation:
There are two kinds of collision; elastic collision and inelastic collision. In an elastic collision, both momentum and kinetic energy are conserved.
However, in an inelastic collision, kinetic energy is not conserved. So, when the bumper of two cars collide, the cars come to a stop because the collision is inelastic.
If you have 5.6 grams of a radioactive isotope with a half-life of 150 years:
How much of the isotope will you have left after 750 years?
Answer:
0.175g
Explanation:
A = A02^-(t/hl)
= (5.6g)2^-(750/150)
= 0.175g
A bicycle with a mass of 100kg hit a wall at an acceleration of 4 m/s2, what is the force?
Answer:
400N
Explanation:
F= ma
F= 100 x 4
F= 400N
The _____is a measure of the number of waves that pass a point in a given amount of time
When 120 V is applied across a 20 m long wire, the magnitude of the current density was found to be 2 * 10 ^ 8 * A / (m ^ 2) . The resistivity of this wire is
Answer:
[tex]\rho=3\times 10^{-8}\ \Omega-m[/tex]
Explanation:
Given that,
Voltage, V = 120 V
The length of the wire, l = 20 m
The current density of the wire, [tex]\dfrac{I}{A}=2\times 10^8\ A/m^2[/tex]
We need to find the resistivity of this wire. We know that,
[tex]R=\rho \dfrac{l}{A}[/tex]
Where
[tex]\rho[/tex] is the resistivity of wire
Also, [tex]R=\dfrac{V}{I}[/tex]
So,
[tex]\dfrac{V}{I}=\rho \dfrac{l}{A}\\\\\rho=\dfrac{V}{l\dfrac{I}{A}}[/tex]
Put all the values,
[tex]\rho=\dfrac{120}{20\times 2\times 10^8}\\\\=3\times 10^{-8}\ \Omega-m[/tex]
So, the resistivity of this wire is equal to [tex]3\times 10^{-8}\ \Omega-m[/tex].
over due by alot please help
Answer:
i would say the third one
Explanation:
may i be brainliest?
Determine the mass of fuel required for the expected energy consumption in the United States for the next 10 years:
Provide the energy use per person per year in the United States = 3.5 × 1011 joules.
Base your calculations on a current population of 310,000,000.
Answer:
(This will depend on the type of fuel, I will assume that the fuel is petrol)
First, let's find the expected energy consumption in the US for the next 10 years.
We know that in one year, a person consumes 3.5*10^11 joules.
There are 310,000,00 people on the US
Then the total consumption in one year is:
310,000,000*3.5*10^11 joules = 1.085*10^20 J
In 10 years the consumption is 10 times the consumption of a single year, then the expected energy consumption in the US for the next 10 years is:
10*1.085*10^20 J = 1.085*10^21 J
Now let's find the mass of fuel required.
We know that a liter of petrol has 31,536,000 joules of energy,
And a liter of petrol weights 0.75 kg
To find the number of liters of petrol that we need, we need to find the quotient between the expected energy consumption in the next 10 years and the energy of a single liter of petrol, this is:
N = (1.085*10^20 J)/(31,536,000 j) = 3.44*10^13
We will need 3.44*10^13 liters of petrol.
And the total mass of petrol will be:
M = 3.44*10^13*0.75 kg = 2.58*10^13 kg of fuel.
A solid metal ball with a mass of 10.0 kg is placed on a smooth floor what force would be needed to accelerate the ball at a rate of 2.0 m/s2.
40 N
20 N
5 N
0.2 N
true or false? rocks have organic materials and fossil remains in them
Answer:
trueeeee
Explanation:
How many snowmen do you think this sled can destroy? Explain your answer.
Answer:
342,690
Explanation:
I think, given 342,690 snowmen down a giant hill, that sled could destroy every single snowman :)
What element is formed in the following nuclear reaction
Answer:
Oxygen or more precisely, the O-15 isotope.
Lack of portion control contributes to the obesity problem in the United States.
True
False
Use the drop-down menu to answer the question.
According to "Take a Closer Look", what type of lens is used to correct nearsightedness?
Answer: A.) concave lens
Explanation: i hope this helps shawtay :)
In general, a concave lens (also known as a diverging lens) is used to correct nearsightedness, as stated in "Take a Closer Look." Option C is correct.
What is the lens?A lens is an optical component that is used to refract (bend) and focus light. It is typically made of a transparent material, such as glass or plastic, and has a specific shape that allows it to alter the path of light as it passes through.
Here,
In general, a concave lens (also known as a diverging lens) is used to correct nearsightedness, as stated in "Take a Closer Look."
A concave lens is thinnest at the center and thicker at the edges, which causes light rays passing through the lens to diverge or spread out. By placing a concave lens in front of a nearsighted eye, the lens causes incoming light rays to diverge more before they reach the eye's lens, which then focuses them properly on the retina, resulting in clearer vision.
Learn more about the lens here:
https://brainly.com/question/2919483
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