Answer:
B, C and D are true.
Explanation:A is false because they appear a pale reddish colour not purple.
4. Describe (in words) the relationship between the distance and time2 as the duster accelerated down the slope, 4.1 with its rough surface in contact with the track
Direct relation is present between distance and time which means one has direct impact on the value of other.
There is direct relationship between distance and time. Direct relation means if one increases the other automatically increases while on the other hand, if one decreases the other will also decreases. If there is a large amount of distance so more time is required to pass it while on the other hand, if there is less distance so less time is required to complete it so we can conclude that there is direct relationship between distance and time.
https://brainly.com/question/24323600
A 650-kg elevator starts from rest. It moves upward for 3.00 s with constant acceleration until it reaches its cruis- ing speed of 1.75 m/s. (a) What is the average power of the elevator motor during this period
Answer: [tex]P=5573.43\ W[/tex]
Explanation:
Given
Mass of the elevator is [tex]M=650\ kg\\\[/tex]
Time period of ascension [tex]t=3\ s[/tex]
cruising speed [tex]v=1.75\ m/s[/tex]
Distance moved by elevator during this time
Suppose Elevator starts from rest
[tex]\Rightarrow v=u+at\\\Rightarrow 1.75=0+a(3)\\\Rightarrow a=0.583\ s[/tex]
Distance moved
[tex]\Rightarrow h=ut+0.5at^2\\\Rightarrow h=0+0.5\times 0.5833\times (3)^2\\\Rightarrow h=2.62\ m[/tex]
Gain in Potential Energy is
[tex]\Rightarrow E=mgh\\\Rightarrow E=650\times 9.8\times 2.62\\\Rightarrow E=16,720.3\ N[/tex]
Average power during this period is
[tex]\Rightarrow P=\dfrac{E}{t}\\\\\Rightarrow P=\dfrac{16,720.3}{3}\\\\\Rightarrow P=5573.43\ W[/tex]
Answer:
The power is 331.7 W.
Explanation:
mass, m = 650 kg
time, t= 3 s
initial velocity, u = 0 m/s
final velocity, v = 1.75 m/s
(a) The power is defined as the rate of doing work.
Work is given by the change in kinetic energy.
W = 0.5 m (V^2 - u^2)
W = 0.5 x 650 x 1.75 x 1.75 = 995.3 J
The power is given by
P = W/t = 995.3/3 = 331.7 W
A fast moving vehicle travelling at a speed of 25.4 m/s comes up behind another vehicle which is
travelling at a slower constant speed of 13.6 m/s. If the faster vehicle does not begin braking until it
is 11.4 meters away from the car in front of it, what is the minimum acceleration that the faster car
must exhibit if it is to avoid colliding with the car in front? Assume that both cars are travelling in the
positive direction
Answer:
a = 6.1 m / s²
Explanation:
For this kinematics exercise, to solve the exercise we must set a reference system, we place it in the initial position of the fastest vehicle
Let's find the relative initial velocity of the two vehicles
v₀ = v₀₂ - v₀₁
v₀ = 25.4 - 13.6
v₀ = 11.8 m / s
the fastest vehicle
x = v₀ t + ½ a t²
The faster vehicle has an initial speed relative to the slower vehicle, therefore it is as if the slower vehicle were stopped, so the distance that must be traveled in a fast vehicle to reach this position is
x = 11.4 m
let's use the expression
v² = v₀² - 2 a x
how the vehicle stops v = 0
a = v₀² / 2x
a = [tex]\frac{11.8^2}{2 \ 11.4}[/tex]
a = 6.1 m / s²
this velocity is directed to the left
Physics question plz help
Answer:
B. [tex]30\,s\,< t \le 40\,s[/tex].
Explanation:
The vehicle is travelling eastwards when its velocity is positive and westwards when velocity is negative. According to the graph, [tex]v > 0[/tex] for [tex]30\,s\,< t \le 40\,s[/tex]. Hence, correct answer is B.
After a successful experiment involving the Sun, an astrophysicist proposes a theory for how stars change during the course of their existence. Is the astrophysicist correct in doing this
Answer:
Yes
Explanation:
A scientific theory is an explanation of a natural phenomenon based on available facts. If an Astrophysicist (a scientist who studies the universe and its celestial constituents) performs several successful experiments about a natural body like the sun and tests the results of his experiment using the principles of maths and physics and they come out as true, then he can propose a scientific theory based on his findings.
Unlike a scientific law that simply states a fact, a scientific theory provides evidence and explanation to support the facts.
A container is filled with water and the pressure at the container bottom is P. If the container is instead filled with a liquid having specific gravity 1.05, what new bottom pressure will be measured
Consider two oppositely charged, parallel metal plates. The plates are square with sides L and carry charges Q and -Q. What is the magnitude of the electric field in the region between the plates
Answer:
E = [tex]\frac{Q}{L^2 \epsilon_o}[/tex]
Explanation:
For this exercise we use that the electric field is a vector, so the resulting field is
E_total = E₁ + E₂ (1)
since the field has the same direction in the space between the planes
Let's use Gauss's law for the electric field of each plate
Let's use a Gaussian surface that is a cylinder with the base parallel to the plate, therefore the normal to the surface and the field lines are parallel and the angle is zero so cos 0 = 1
Ф = ∫ .dA = [tex]q_{int}[/tex] /ε₀
if we assume that the charge is uniformly distributed on the plate we can define a charge density
σ = q_{int} A
as the field exists on both sides of the plate on the inside
E A = A σ / 2ε₀
E = σ / 2ε₀
we substitute in equation 1
E = σ /ε₀
for the complete plate
σ = Q / A = Q / L²
we substitute
E = [tex]\frac{Q}{L^2 \epsilon_o}[/tex]
Which of the following careers would physicists be least qualified to perform,
based on their training?
A. Artist
B. Mechanical engineer
C. Laser designer
D. Power plant engineer
write a note on unity of ant
Answer: When a pathogen enters their colony, ants change their behavior to avoid the outbreak of disease. In this way, they protect the queen, brood and young workers from becoming ill. These results, from a study carried out in collaboration between the groups of Sylvia Cremer at the Institute of Science and Technology Austria (IST Austria) and of Laurent Keller at the University of Lausanne, are published today in the journal Science.
Explanation: search for it.
If the accuracy in measuring the position of a particle increases, the accuracy in measuring its velocity will Group of answer choices remain the same. decrease. increase. It is impossible to say since the two measurements are independent and do not affect each other.
Answer:
The correct answer is Option A (decrease).
Explanation:
According to Heisenberg's presumption of unpredictability, it's impossible to ascertain a quantum state viewpoint as well as momentum throughout tandem.Also, unless we have accurate estimations throughout the situation, we will have a decreased consistency throughout the velocity as well as vice versa though too.Other given choices are not connected to the given query. Thus the above is the right answer.
In a physics lab, light with a wavelength of 560 nm travels in air from a laser to a photocell in a time of 17.2 ns . When a slab of glass with a thickness of 0.810 m is placed in the light beam, with the beam incident along the normal to the parallel faces of the slab, it takes the light a time of 20.8 ns to travel from the laser to the photocell.
Required:
What is the wavelength of the light in the glass?
Answer:
Distance traveled = 3 * 10E8 * 17.2 * 10E-9 = 5.16 m
.81 / 3 * 10E8 = 2.7 * 10E-9 normal time thru glass
(20.8 - 17.2) * E10-9 = 3.6 * 10E-9 additional time due to glass
c tg = c n ta where tg and ta are the times spent in glass and air
(Note you can also write Va = n Vg or D / ta = n D / tg)
n = tg / ta = 3.6 / 2.7 = 1.33 the index of refraction of the glass
Wavelength (air) = Wavelength (glass) * n
Wavelenght = 560 nm / 1.33 = 421 nm
A 59.0 kg bungee jumper jumps off a bridge and undergoes simple harmonic motion. If the period of oscillation is 0.250 mins, what is the spring constant (in N/m) of the bungee cord, assuming it has negligible mass compared to that of the jumper
Answer:
The spring constant of the spring is 10.3 N/m.
Explanation:
Given that,
Mass of a bungee jumper, m = 59 kg
The period of oscillation, T = 0.25 min = 15 sec
We need to find the spring constant of the bungee cord. We know that the period of oscillation is given by :
[tex]T=2\pi\sqrt{\dfrac{m}{k}}[/tex]
Where
k is the spring constant
[tex]T^2=4\pi^2\times \dfrac{m}{k}\\\\k=4\pi^2\times \dfrac{m}{T^2}\\\\k=4\pi^2\times \dfrac{59}{(15)^2}\\\\k=10.3\ N/m[/tex]
So, the spring constant of the spring is 10.3 N/m.
A baseball pitcher throws a fastball by spinning his arm at 27.7m/s. The ball has a mass of 0.700kg and experiences a net centripetal force of 625N. How long is the pitchers arm (the radius of the curve)?
In the historical sense, postmodern society is simply a society that occurs after the modern society. ... Many of the elements of a society like this are reactions to what the modern society stood for: industrialism, rapid urban expansion, and rejection of many past principles.
This percentage of all water on the planet is salt water . 97 % 95% 93% 91%
hurry please !
Answer:
none of those are right, its technically 96.5%. so i would say 97% is your best bet because thats closest and it just rounds up :)
Explanation:
A spring of stiffness 11000 N/m is connected to a wall. The other end is attached to a block of mass 2 kg. A second spring of stiffness 12200 N/m extends between the first block and a second block of mass 2 kg. You are holding the second block with 300 N of force and everything is motionless.
Required:
How stretched is the spring connecting the first block to the wall?
Answer:
Explanation:
Let the stretch produced in first spring and second spring be x₁ and x₂ respectively. 300 N is the restoring force created in them .
k₁x₁ = k₂x₂ = 300 N .
k₁ = 11000 N/m
11000 x₁ = 300N
x₁ = 300 N / 11000
= 0.027 m
= 2.7 cm .
Set the initial bead height to 3.00 m. Click Play. Notice that the ball makes an entire loop. What is the minimum height required for the ball to make an entire loop
Answer:
h> 2R
Explanation:
For this exercise let's use the conservation of energy relations
starting point. Before releasing the ball
Em₀ = U = m g h
Final point. In the highest part of the loop
Em_f = K + U = ½ m v² + ½ I w² + m g (2R)
where R is the radius of the curl, we are considering the ball as a point body.
I = m R²
v = w R
we substitute
Em_f = ½ m v² + ½ m R² (v/R) ² + 2 m g R
em_f = m v² + 2 m g R
Energy is conserved
Emo = Em_f
mgh = m v² + 2m g R
h = v² / g + 2R
The lowest velocity that the ball can have at the top of the loop is v> 0
h> 2R
What is the total kinetic energy of a 0.15 kg hockey puck sliding at 0.5 m/s and rotating about its center at 8.4 rad/s
Answer:
[tex]K=0.023J[/tex]
Explanation:
From the question we are told that:
Mass [tex]m=0.15[/tex]
Velocity [tex]v=0.5m/s[/tex]
Angular Velocity [tex]\omega=8.4rad/s[/tex]
Generally the equation for Kinetic Energy is mathematically given by
[tex]K=\frac{1}{2}M(v^2+\frac{1}{2}R^2\omega^2)[/tex]
[tex]K=\frac{1}{2}0.15(0.5^2+\frac{1}{2}(0.038)^2.(8.4rad/s^2))[/tex]
[tex]K=0.023J[/tex]
1/012=1/0.05+1/d' hiiiiiiiiii
Correct question is;
1/0.12 = (1/0.05) + (1/d')
Answer:
d' = -1/700
Explanation:
1/0.12 = (1/0.05) + (1/d')
Let's rearrange to get;
(1/d') = (1/0.12) - (1/0.05)
(1/d') = (1/(12/100)) - (1/(5/100))
(1/d') = 100/12 - 100/5
Let's multiply through by 60 to get rid of the denominators on the right side;
> (1/d') = 500 - 1200
> (1/d') = -700
> d' = -1/700
12. A car travels in a straight line with an average velocity of 80 km/h for 2.5h and then an average velocity of 40 km/h from 1.5 h (a) what is the total displacement for the 4 h trip? (b) What is the average velocity for the total trip?
Answer:
a. Total displacement = 140 km/h
b. Average velocity = 35 km/h
Explanation:
Given the following data;
Average velocity A = 80 km/h
Time A = 2.5 hours
Average velocity B = 40 km/h
Time B = 1.5 hours
a. To find the total displacement for the 4 h trip;
Total time = Time A + Time B
Total time = 2.5 + 1.5
Total time = 4 hours
Next, we would determine the displacement at each velocity.
Mathematically, displacement is given by the formula;
Displacement = velocity * time
Substituting into the formula, we have;
Displacement A = 80 * 2.5
Displacement A = 200 km/h
Displacement B = 40 * 1.5
Displacement B = 60 km/h
Total displacement = Displacement A - Displacement B
Total displacement = 200 - 60
Total displacement = 140 km/h
b. To find the average velocity for the total trip;
Mathematically, the average velocity of an object is given by the formula;
[tex] Average \; velocity = \frac {total \; displacement}{total \; time} [/tex]
Substituting into the formula, we have;
[tex] Average \; velocity = \frac {140}{4} [/tex]
Average velocity = 35 km/h
list the factors that affecting frictional force ?
Answer:
The frictional force between two bodies depends mainly on three factors: (I) the adhesion between body surfaces (ii) roughness of the surface (iii) deformation of bodies
Which wave has the smallest amplitude?
I will give brainliest to the right answer.
Wave-D (the red one) has the smallest amplitude of the 4 waves on this graph.
A small object with mass 0.20 kg swings as a pendulum on the end of a long light rope. For small amplitude of swing, the period of the motion is 3.0 s. If the object is replaced by one with mass 0.400 kg, what is the period for small amplitude of swing? (a) 1.5 s (b) 3.05 (c) 6.0 s (d) 12.0 s (e) none of the above answers
Answer:
The correct option is (e) "none of the above".
Explanation:
Given that,
A small object with mass 0.20 kg swings as a pendulum on the end of a long light rope. For small amplitude of swing, the period of the motion is 3.0 s.
If the object is replaced by one with mass 0.400 kg, then we have to find the period for small amplitude of the swing.
We know that the time period can be calculated as :
[tex]T=2\pi \sqrt{\dfrac{l}{g}}[/tex]
Where
l is the length
g is acceleration due to gravity
It means the time period is independent of the mass. So, if the mass is replaced by one with mass 0.400 kg, there is no effect on the time period.
Which formula represents a hydrocarbon?
CaO2
CH2O
C5H12
H2SO4
1L of a solution of oxalic acid [(). ] contains 2.52g of acid.
Calculate the molarity of the solution.
Answer:
0.028 M.
Explanation:
NOTE: This question is a chemistry question. However, the answer to the question can be obtained as shown below:
We'll begin by calculating the number of mole in 2.52 g of oxalic acid, C₂H₂O₄. This can be obtained as follow:
Mass of C₂H₂O₄ = 2.52 g
Molar mass of C₂H₂O₄ = (2×12) + (2×1) + (4×16)
= 24 + 2 + 64
= 90 g/mol
Mole of C₂H₂O₄ =?
Mole = mass / molar mass
Mole of C₂H₂O₄ = 2.52 / 90
Mole of C₂H₂O₄ = 0.028 mole
Finally, we shall determine the molarity of the solution. This can be obtained as follow:
Mole of C₂H₂O₄ = 0.028 mole
Volume = 1 L
Molarity =?
Molarity = mole / Volume
Molarity = 0.028 / 1
Molarity = 0.028 M
Therefore, the molarity of the solution is 0.028 M.
what is threshold of hearing?
-> The minimum sound pressure level at which a sound of a given frequency can be perceived by the human ear is known as threshold of hearing.
Explanation:
The absolute threshold of hearing is the minimum sound level of a pure tone that an average human ear with normal hearing can hear with no other sound present. The absolute threshold relates to the sound that can just be heard by the organism.
Which best describes what occurs when an object takes in a wave as the wave hits it?
A. transmission
B. absorption
C. reflection
D. refraction
Answer:
B
Explanation:
ABSORPTION
i need help..........
Answer:
I hope this will help you. i tried my best
The following are ways to properly manage your stress except
Answer:
you should provide the options for us to answer?
On a cello, the string with the largest linear density (1.44 x 10-2 kg/m) is the C string. This string produces a fundamental frequency of 93.0 Hz and has a length of 0.834 m between the two fixed ends. Find the tension in the string.
Answer:
[tex]T=346.5N[/tex]
Explanation:
From the question we are told that:
Density [tex]\rho= (1.44 * 10^{-2} kg/m)[/tex]
Frequency[tex]F=93.0Hz[/tex]
Length[tex]l=0.834m[/tex]
Generally the equation for Frequency is mathematically given by
[tex]F=\frac{1}{2 l}sqrt{\frac{T}{\rho}}[/tex]
Therefore
[tex]T=\rho(2 lF)^2[/tex]
[tex]T= (1.44 * 10^{-2}*(2*0.834)(93.0))^2[/tex]
[tex]T=346.5N[/tex]
Compare and contrast how sound waves behave when they
encounter solid hard surfaces
encounter soft surfaces
pass through an opening
encounter a barrier
Answer:
They sound tinkling in solid hard like metal.
They can vibrate soft surface
I could just Ans this
