This question is incomplete because the options are missing; here is the complete question:
A runner starts at point A, runs around a 1-mile track, and finishes the run back at point A. Which of the following statements is true?
A. The runner's displacement is 1 mile.
B. The runner's displacement is zero.
C. The distance the runner covered is zero.
D. The runner's speed was zero.
The answer to this question is B. The runner's displacement is zero
Explanation:
Displacement always implies a change of position; this means an object or individual moves from point A to point B, and therefore the original position is different from the final position. Additionally, in displacement, other related factors such as the total distance the body moved and the direction of movement. In the case presented, it can be concluded there was no displacement or the displacement is zero because even when the runner moved and ran two miles, he returned to the initial position, and without a change in the position, there is no displacement.
What is electrical power in terms of current and potential difference? Explain.
Answer:
Ohm's Law:
[tex]V = IR[/tex]
Where V is voltage, I is current and R is resistance
While,
[tex]P = IV[/tex]
Where P is power, I is current and V is voltage (or potential difference)
So, Electrical power is the product of current and potential difference.
HURRY!!!!
Fred and Ted are racing cars down a frictionless track with a jump at the bottom
when suddenly an argument breaks out. Fred says, “If we release the cars from a
point twice as high as we are currently doing so, the cars will have twice the
gravitational potential energy, and therefore be travelling twice fast when they hit
the jump." Ted says, “In order to double the speed of the cars when they hit the
ramp, I think we will have to more than double the height!" Who is right? Prove it!
Answer:
Ted is correct
Explanation:
The equation for gravitational potential energy is PE = m·g·h
The equation for gravitational kinetic energy is KE = 1/2·m·v²
Where:
m = Mass of the object (The racing car)
g = Acceleration due to gravity
h = The height to which the object is raised
v = Velocity of motion of the object
From the principle of conservation of energy, energy can neither be created nor destroyed but changes from one form to another, we have;
Potential energy gained from location at height h = Kinetic energy gained as the object moves down the level ground
m·g·h = 1/2·m·v² canceling like terms gives
g·h = 1/2·v²
v = (√2·g·h)
If the speed is doubled, we have
2·v = 2× (√2·g·h) = (√2·g·4·h)
Therefore, if 2·v = v₂ then v₂ = (√2·g·4·h)
Since g, the acceleration due to gravity, is constant, it means that the initial height must be multiplied or increased 4 times to get the new height, that is we have;
v₂ = (√2·g·4·h) = (√2·g·h₂)
Where:
4·h = h₂
Which gives;
v₂² = 2·g·h₂
1/2·v₂² = g·h₂
1/2·m·v₂² = m·g·h₂ Just like in the first relation
Therefore, Ted is correct s they need to go up four times the initial height to double the speed.
The count rate of a radioactive source decreases from 1600 counts per minute to 400 counts per minute in 12 hours. What is the half-life of the source?
Answer:
[tex]t_{1/2}=6 h[/tex]
Explanation:
Let's use the decay equation.
[tex]A=A_{0}e^{-\lambda t}[/tex]
Where:
A is the activity at t timeA₀ is the initial activityλ is the decay constantWe know that [tex]\lambda=\frac{ln(2)}{t_{1/2}}[/tex]
So we have:
[tex]\lambda=\frac{ln(A/A_{0})}{t}[/tex]
[tex]\frac{ln(2)}{t_{1/2}}=\frac{ln(A/A_{0})}{t}[/tex]
[tex]t_{1/2}=\frac{t*ln(2)}{ln(A/A_{0})}[/tex]
[tex]t_{1/2}=6 h[/tex]
Therefore, the half-life of the source is 6 hours.
I hope it helps you!
Un resorte se alarga 5 cm bajo la acción de una fuerza de 39,2 N. ¿Cuál es la constante del resorte? Si ahora la fuerza es 68,6 N. ¿Cuál es el nuevo alargamiento?
Answer:
[tex]k=784 N/m[/tex]
[tex]\Delta x=8,8 cm[/tex]
Explanation:
Usando la ley de Hook tenemos:
[tex]F=k\Delta x[/tex]
Solving it for k we have:
[tex]k=\frac{F}{\Delta x}[/tex]
[tex]k=\frac{39,2}{0,05}[/tex]
[tex]k=784 N/m[/tex]
Usando la misma ecuación y sabiendo k tenemos:
[tex]\Delta x=\frac{F}{k}[/tex]
[tex]\Delta x=\frac{68,6}{784}[/tex]
[tex]\Delta x=8,8 cm[/tex]
Espero esto te ayude!
One sprinter has a stride of 120cm, another 75cm. How many steps do they each take if they run a 100m race?
Explanation:
100 m / (1.20 m) = 83.3
100 m / (0.75 m) = 133.3
Rounded up, the first sprinter takes 84 steps, and the second sprinter takes 134 steps.
a body starts from rest and gains the velocity of 5 metre per second into second is it of uniform velocity explain
Answer:
It is not a uniform velocity, because his velocity increases for 5 m every second (acceleration = 5m/s2), meaning his velocity always changes.
When he starts at rest, his velocity is 0 m/s. But in 1 second later, his velocity is already 5m/s. At 2 seconds, his velocity will be 10 m/s.
A car travels 500m in 50s, then 1,500m in 75s. Calculate its averages speed for the whole journey
Answer:
15m/s
Explanation:
500 ÷ 50 = 10m/s
1500 ÷ 75 = 20m/s
10 + 20 = 30
30 ÷ 2 = 15m/s
Answer: 16 miles per second
Explanation:
Find the total distance traveled and the total time.
[tex]\text{average rate}=\dfrac{1500+500}{75+50}=\dfrac{2000\ miles}{125\ second}=\large\boxed{16\ mps}[/tex]
A boy is twirling a model airplane on a string 4 feet long. if he twirls the plane at 0.25 revolutions per minute, how far does the plane travel in 4 minutes? round to the nearest tenth.
Answer:
25.13 ft
Explanation:
r = 4 feet
ω=0.25 revolution per minute
=1 revolution in 4 minutes
total number of revolution N = 1 (in 4 minutes )
v=rω
distance traveled = 2×N×π×r
=2×1×π×4
=8π
= 25.13ft in 4mins
N2 + O2 → 2NO N-N triple bond: 941 kJ/mol O-O double bond: 495 kJ/mol N-O bond: 201 kJ/mol
Answer:
[tex]\large \boxed{\text{761 kJ}}[/tex]
Explanation:
You calculate the energy required to break all the bonds in the reactants.
Then you subtract the energy needed to break all the bonds in the products.
N₂ + O₂ ⟶ 2NO
N≡N + O=O ⟶ 2O-N=O
Bonds: 2N≡N 1O=O 2N-O + 2N=O
D/kJ·mol⁻¹: 941 495 201 607
[tex]\begin{array}{rcl}\Delta H & = & \sum{D_{\text{reactants}}} - \sum{D_{\text{products}}}\\& = & 2 \times 941 +1 \times 495 - (2 \times 201 + 2\times 607)\\&=& 2377 - 1616\\&=&\textbf{761 kJ}\\\end{array}\\\text{The enthalpy of reaction is $\large \boxed{\textbf{761 kJ}}$}.[/tex]
the most common mineral group is broken into the subgroups of ferromagnesium and nonferromagnesium
Answer:
They're made of silicon and oxygen.
Explanation:
An object in a certain direction with an acceleration in the perpendicular direction
Answer:
An object moving in certain direction with an acceleration in the perpendicular direction. The above condition is possible . Example of such situation in life would be when stone tied to a string whirling in a circular path
Hope this helps and pls mark as BRAINLIEST :)
PLEASE I NEED HELP WITH THIS ASAP
A student finds a rock on the way to school. In the laboratory he determines that the volume of the rock by placing the rock in a graduated cylinder with 50 cm3 of water and watched the water rise to 72.7 cm3. The student determined the mass is 39.943 g through the use of a triple beam balance. What is the density of the rock?
With step by step explanation
Answer:
density=mass/volume
39.943/22.7=1.75
Explanation:
*SS2 E_CAT 2020*
*DATE:* FRIDAY, 3RD JULY 2020
*Time allowed:* 40 minutes
*Instruction*: Attempt all questions. Send screenshots of solutions to my number *privately*.
*Take:* specific heat capacity of water = 4200 J/kgK
1. The lower and upper fixed points of a mercury-in-glass thermometer are marked X and 180mm respectively. On a particular day, the mercury meniscus in the thermometer rises to 60mm. If the corresponding reading on a Celsius scale is 20°C, what is the value of X?
2. A resistance thermometer has a resistance of 20 ohm at 0°C and 85 ohm at 100°C. If its resistance is 52 ohm in a medium, calculate the corresponding temperature.
3. A tap supplies water at 26°C while another supplies water at 82°C. If a man wishes to bath with water at 40°C, what is the ratio of the mass of hot water to that of cold water.
4. A metal of mass 1.55kg was heated from 300K to 320K in 6 minutes by a boiling ring of 85 W rating, calculate the specific heat capacity of the metal. {Neglect heat losses to the surrounding.}
5. (i) What is meant by the statement, _the specific heat capacity of copper is 400 J/KgK? (ii) Distinguish between specific heat capacity and thermal capacity deriving the mathematical relationship between.
thank you
Explanation:
2. Heat gained by tap1 = mass1 × SHC × change in temperature
= mass1 × 4200 × (40 - 26)
= mass1 × 58800
Heat lost by tap 2 = mass2 × SHC × change in temperature
= mass2 × 4200 × (82 - 40)
= mass2 × 176400
Heat gained = heat lost
mass1 × 58800 = mass2 × 176400
Ratio of mass 1 to mass 2 = 58800mass1 : 176400mass2
= 1 : 3
Three 15.0-W resistors are connected in parallel across a 30.0-V battery. Please show all work.
a) Find the current through each branch of the circuit.
b) Find the equivalent resistance of the circuit.
c) Find the current through the battery.
Answer:
Part A)
Since all of the resistors have equal resistance, hence for finding even only 1 branch It will be fine because current will be the same for all branches.
=> [tex]I = \frac{V}{R_{1} }[/tex]
=> [tex]I = \frac{30}{15}[/tex]
=> I = 2 A
Part B)
Equivalent resistance for parallel circuits is the sum of reciprocals of each resistor.
=> [tex]\frac{1}{R} = \frac{1}{R_{1}}+\frac{1}{R_{2}} +\frac{1}{R_{3}}[/tex]
=> [tex]\frac{1}{R} = \frac{1}{15}+ \frac{1}{15}+\frac{1}{15}[/tex]
=> [tex]\frac{1}{R} = \frac{3}{15}[/tex]
=> R = 15/3
=> R = 5 ohms
Part C)
I = V/R
Where I is current, V is voltage and R is the equivalent resistance
=> I = 30/5
=> I = 6 A
as a motorcycle takes a sharp turn the type of motion that occurs is called ——— motion
Answer:
circular motion
Explanation:
hope this helps you :)
Answer:
Centripetal motion
Explanation:
As a motorcycle takes a sharp turn the type of motion that occurs is called centripetal motion
describe briefly one problem caused by the expansion of metals.
Answer:
The expansion and contraction of materials can also cause problems. For example, bridges expand in the summer heat and need special joints to stop them bending out of shape.A bimetallic strip has two metal strips glued together. One of these metals expands more for each degree temperature rise than that other.
How is it possible to blow a balloon?
Explanation:
To blow up a balloon, start by pinching the neck of the balloon with your index finger and thumb. Then, take a deep breath and put the opening of the balloon in between your lips. When you're ready, loosen your grip on the neck and blow into the balloon opening so the balloon starts to fill with air.May
A runner starts from rest and speeds up with constant acceleration. If she
has gone a distance of 30 m at the point when she reaches a speed of 8 m/s,
what is her acceleration?
A. 7.5 m/s2
B. 3.8 m/s2
C. 9.1 m/s2
D. 1.1 m/s2
Answer:
a = 1.07 m/s^2
Explanation:
The computation of the acceleration is shown below:
As we know that
[tex]v_f^{2} - v_i^{2} = 2 ad[/tex]
where,
v_i = 0 m/s = initial speed
v f = 8 m/s = final speed
d = 30m = distance
Now placing these values to the above equation
[tex]8^{2} - 0 = 2 \times a \times 30[/tex]
64 = 60a
a = 1.07 m/s^2
We simply applied the above formula so that we could able to determine the acceleration
A man can walk three blocks east and four blocks north in 20 min. He can drive 12 times that distance in the same amount of time. How far can the man
drive in 20 min? Assume that each block is 0.3 kilometers.
Answer: 25.2 km
Explanation:
3 blocks east and four blocks east = 7 blocks
1 block = 0.3 km --> 7 blocks = 2.1 km
12 times 2.1 km = 25.2 km
A hydrogen bond is a special form of a(n)
a. covalent bond.
b. dipole-dipole force.
C. ionic bond.
d. London dispersion force.
Answer:
B
Explanation:
How is mercury barometer constructed ?
Answer:
A mercury barometer is a device use to measure stomspheric pressure and is constructed as following:
A mercury barometer requires a tube which has one close end, and one open end.Tube is placed upside down in a beaker in such a way so that one end open in the beaker and the other remain outside of the beaker. The barometric liquid (mercury) is then filled in the tube by pouring mercury liquid in the beaker.The position of tube creates vacuum between the closed end of the tube and liquid surface and the Mercury has high density that is why used as the liquid to measure pressure.
Before beginning an experiment, Mrs. Wilson warns her science class not to drop the bar magnets on the floor. What is the most likely reason for Mrs. Wilson’s warning?
Answer:
we should not drop a magnet on the floor because the magnets tend to lose magnetism gradually and become weak over a period of time if they are not stored properly.
Answer:
Well depending on the floor like say if it was a wooden floor the magnet might lose it magnetism, if concrete floor the magnetic brake and still lose it magnetism, if a metal floor the magnet would stick not sure if it wood lose it magnetism or not but the possibilities still there, basically what I'm saying is the magnet would lose its magnetism if it were to interact with the floor maybe temporary or maybe permanently.
for those with with a learning disability it's a
Explanation:
How far away from the surface of earth does the acceleration due to gravity will be inclined by 36% of its value on the surface of earth? Radius of earth is 6400 km
Answer:
1,600 km
Explanation:
since the acceleration due to gravity reduces by 36%, it means that (1 - 36%) of acceleration still remains:
g' = 64g/100
using the acceleration formula:
g' = g x [R² / (R + height)²]
64g/100 = g x [R² / (R + height)²]
64/100 = R² / (R + height)²
√(64/100) = √[R² / (R + height)²]
8/10 = R / (R + height)
8 (R + height) = 10R
8R + 8height = 10R
8height = 2R
height = 2R / 8 = R / 4
R = 6,400 km
height = 6,400 km / 4 = 1,600 km
Answer:
The acceleration due to gravity will be inclined 1600 KM by 36% of its value on the surface of earthA gas occupies a volume of 1.0 m3 in a cylinder at a pressure of 120kPa. A piston compresses the gas until the volume is 0.25m3, the temperature remaining constant. What is the new pressure of the gas?
Answer:
Approximately [tex]480\; \rm kPa[/tex], assuming that this gas is an ideal gas.
Explanation:
Let [tex]V(\text{Initial})[/tex] and [tex]P(\text{Initial})[/tex] denote the volume and pressure of this gas before the compression. Let [tex]V(\text{Final})[/tex] and [tex]P(\text{Final})[/tex] denote the volume and pressure of this gas after the compression.By Boyle's Law, the pressure of a sealed ideal gas at constant temperature will be inversely proportional to its volume. Assume that this gas is ideal. By this ideal gas law:
[tex]\displaystyle \frac{P(\text{Final})}{P(\text{Initial})} = \frac{V(\text{Initial})}{V(\text{Final})}[/tex].
Note that in Boyle's Law, [tex]P[/tex] is inversely proportional to [tex]V[/tex]. Therefore, on the two sides of this equation, "final" and "initial" are on different sides of the fraction bar.
For this particular question:
[tex]V(\text{initial}) = 1.0\; \rm m^3[/tex].[tex]P(\text{Initial}) = 120\; \rm kPa[/tex].[tex]V(\text{final}) = 0.25\; \rm m^3[/tex].The pressure after compression, [tex]P(\text{Final})[/tex], needs to be found.Rearrange the equation to obtain:
[tex]\displaystyle P(\text{Final}) = \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})[/tex].
Before doing any calculation, think whether the pressure of this gas will go up or down. Since the gas is compressed, collisions between its particles and the container will become more frequent. Hence, the pressure of this gas should increase.
[tex]\begin{aligned}P(\text{Final}) &= \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})\\ &= \frac{1.0\; \rm m^{3}}{0.25\; \rm m^{3}} \times 120\; \rm kPa = 480\; \rm kPa\end{aligned}[/tex].
I NEED HELP PLEASE, THANKS! :)
Generate an explanation for the following formula: P = I²R . Explain.
Answer:
P = VI = (IR)I = I2R
Explanation:
What the equation means is that if you double the current you end up with 4 times the power loss. It's like the area of carpet you need for a room - if you make the room twice as long and twice as wide you need 4x as much carpet. The physical explanation is that the voltage difference along a wire depends on the current - more current flowing with a resistance means more voltage (pressure of electricity if you like) is built up.
This extra voltage means more power. So if you double the current your would double the power, but you also double the voltage which doubles the power again = 4x as much power. P = VI = (IR)I = I2R
I hope this helps you out, if I'm wrong, just tell me.
As I mentioned earlier, Ohm's law gives us the formula P = IV, where V is the voltage ( also known as the electrical potential difference ) and I is the current. It is confusing that P = I²R and P = IV are one in the same - so I want to go a bit deeper on that.
We have three formulas, P = IV, P = I²R, and P = V² / R. Each are considered the same. The two formulas P = I²R, and P = V² / R are derived from the statement that P = IV, under the condition V = IR. Substitute the value of V from this second condition V = IR into P = IV. You would get the following -
P = I( IR ),
P = I²R
That is how one can derive the formula P = I²R, and how P = IV and P = I²R are thought to be one in the same. If you would like, take a look at how to get the formula " P = V² / R, "
V = IR, P = IV
I = V / R, P = IV
P = ( V / R )V,
P = V² / R
Hope that helps!
A friend of yours who has not taken an astronomy class looks at your textbook and really likes the picture of the Pleiades, a cluster of stars surrounded by a bluish reflection nebula. She wants to know what causes that beautiful blue glow. To explain it to her, you want to compare the process that causes the blue glow to something that is in your friend's everyday experience. Which of the following terrestrial phenomena is the result of the same type of process that makes a reflection nebula in space?
A. the blueish glow of the flame on a gas stove
B. the blue light you see reflected from a blue sweater
C. the blue colour of the Earth's sky
D. the blue-white colour of the hottest stars
E. the blue feeling you get when you don't do well on an astronomy exam
Answer:
C. the blue colour of the Earth's sky
Explanation:
The Pleiades is a cluster of sister stars that are among the closest star cluster to earth.
The reflection nebula of the Pleiades is due to the scattering of the blue light from the hot blue luminous stars that dominate the star cluster. Th blue light is scattered from dust molecules, thought to be predominantly carbon compound like diamond dusts, and other compounds like iron.
The blue colour of the Earth's sky is the closest terrestrial phenomenon to the reflection nebula. On a clear cloudless day, molecules in the air scatter the blue component of light more than the other component colours of white light, giving the sky its characteristic blue coluor.
The common characteristics of the luminous nebula and the Earth's blue sky is that they both have their light scattered by the presence of small particles.
The center of a bar magnet whose magnetic dipole moment is <6,0,0> A·m2 is located at the origin. A second bar magnet whose magnetic dipole moment is <7, 0, 0> A·m2 is located at 0.23 m. What is the vector force on the second magnet due to the first magnet? (Express your answer in vector form.)
Complete Question
The complete question is shown on the first uploaded image
Answer:
The force is [tex]\= F = (-0.001089, 0 ,0)[/tex]
Explanation:
From the question we are told that
The magnetic dipole moment of first magnet is [tex]z_1 = (6,0,0) A \cdot m^2[/tex]
The magnetic dipole moment of second magnet is [tex]z_2 = (7,0,0) A \cdot m^2[/tex]
The location of the second magnetic dipole moment is [tex]x = 0.39 \ m[/tex]
Generally the vector force on the second magnet due to the first is mathematically evaluated as
[tex]\= F =- \frac{\mu_o }{4 \pi} * \frac{6 * z_1 * z_2}{x^4}[/tex]
Where [tex]\mu _o[/tex] is the permeability of free space with value [tex]4\pi * 10^{-7} N/A^2[/tex]
substituting values
[tex]\= F = - \frac{ 4\pi * 10^{-7} }{4 \pi} * \frac{6 * 6 * 7}{0.39^4}[/tex]
[tex]\= F = (-0.001089, 0 ,0)[/tex]
Note the negative sign show that the force is an attraction force
A car of mass 800 kg is moving at a uniform velocity of 72 km/hr. Find its
momentum.
[Ans: 16000 kgm/s)
A body of mass 5 kg has momentum of 125 kg m/s. Find the velocity of the body
in motion.
[Ans: 25 mls)
Answer:
hope its helpful to uh...
Newton’s third law of motion says that for every action there is a(n) and opposite reaction.
Answer:
for every action thete is an equal and opposite reaction
Answer:
Newton’s third law of motion says that for every action there is a(n)
equal and opposite reaction.
Explanation:
just got it right edg 1928
Q- A body is acted upon by two forces 30N due east and 40N due North. Calculate
resultant and its direction.
Answer:
the following image will make you understand
Explanation: