Answer:
[tex]\boxed{\text{\sf \Large 3.0 s}}[/tex]
Explanation:
Use distance formula
[tex]\displaystyle d=ut+\frac{1}{2} at^2[/tex]
[tex]u= \text{\sf initial velocity}\\d= \text{\sf distance}\\a= \text{\sf acceleration}\\t= \text{\sf time taken}[/tex]
[tex]\displaystyle 18=0 \times t+\frac{1}{2} \times 4 \times t^2[/tex]
[tex]t=3[/tex]
A block starting from rest slides down the length of an 18 m plank with an acceleration of 4.0 meters per second square. Time taken by the block to reach at the bottom is 3 sec.
What is acceleration?The rate at which an object changes its velocity is known as acceleration. Acceleration is a vector quantity. If an object's velocity is changing then it is accelerating and an object with a constant velocity is not accelerating.
The speed at which something moves in a specific direction is known as its velocity. As an illustration, think of the speed of a car travelling north on a highway or the speed at which a rocket takes off.
Given that in the question block slides down an 18 m plank length with an acceleration of 4.0 meters per second square when it begins at rest.
Using equation of motion,
S = ut + (1/2)at²
s is distance, s = 18 m
u is initial velocity, u = 0
a is acceleration, a = 4 m/sec²
t is time
18 = 0*t + (1/2)*4*t
solving we get t = 3 sec.
Time taken by the block to reach at the bottom is 3 sec.
To learn more about acceleration refer to the link:
brainly.com/question/12550364
#SPJ2
Which one is it? Help ASAP
Answer:
extreme heat, because no physical damage can demagnetize a magnet
Explanation:
Answer:
the 3rd one
Explanation:
A ball is dropped off the side of a bridge,
After 1.55 S, how far has it fallen?
(Unit=m)
Answer:
Distance S = 11.77 m (Approx.)
Explanation:
Given:
Time t = 1.55 Second
Gravity acceleration = 9.8 m/s²
Find:
Distance S
Computation:
S = ut + (1/2)(g)(t)²
S = (0)(1.55) + (1/2)(9.8)(1.55)²
S = (0)(1.55) + (1/2)(9.8)(1.55)²
Distance S = 11.77 m (Approx.)
Build a second circuit with a battery and a light bulb but this time add a switch. Your circuit might look something like the one at right. When a switch is open in a circuit, it means the two ends are disconnected and current cannot flow between them. When a switch is closed in a circuit, it means the two ends are connected and current can flow between them. Play with the switch to check how it affects the flow of current. With the switch closed, compare the brightness of the bulb and the flow of current in this circuit, with that of your first circuit. Did increasing the length of wire in the circuit change the brightness of the bulb or the curr
Answer:
the resistance of the wire has no effect on the brightness of the bulb.
Explanation:
Let's apply ohm's law for your light bulb circuit plus wires plus switch
V = I R_{bulb} + I R_ {wire}
the current in a series circuit is constant
V = I (R_{bulb} + R_{wire})
To know the effect of the wires on the brightness of the bulb, we must look for the value of the typical resistance of these elements.
Incandescent bulb
Power 60 W
let's use the power ratio
P = V I = V2 / R
R = V2 / P
the voltage value for this power is V = 120 V
R = 120 2/60
R_bulb = 240 Ω
Resistance of a 14 gauge copper wire (most used), we look for it on the internet
R = 8.45 Ω/ km
in a laboratory circuit approximately 2 m is used, so the resistance of our cable is
R = 8.45 10⁻³ 2
R_wire = 0.0169 Ω
let's buy the two resistors
R_{bulb} = 240
R_{wire} = 0.0169
[tex]\frac{R_{bulb} }{R_{wire} } = \frac{240 }{ 0.0169}[/tex]
[tex]\frac{ R_{bulb} }{ R_{wire} } = 1.4 \ 10^4[/tex]
therefore resistance of the bulb is much greater than that of the wire, therefore almost all the power is dissipated in the bulb.
In summary, the resistance of the wire has no effect on the brightness of the bulb.
What is your hypothesis (or hypotheses) for this experiment?
(about Thermal Energy Transfer)
Answer:
I hypothesis that the motion involving the balls in the experiment were moving to create data.
Explanation:
I hope this helps!
A kite 40 ft above the ground moves horizontally at a constant speed of 10 ft/s, with a child, holding the ball of kite string, standing motionless on the ground. Assume the kite is flying away from the child. At what rate is the child releasing the string when (a) 50 ft of the string is out
Answer:
v = 27.28 m /s, θ = 63.9º
Explanation:
For this exercise we can approximate the movement to a projectile launch, let's analyze the situation.
* We must find the horizontal speed, for this we will find the descent time and the horizontal distance
* We look for the vertical speed
At the highest point the speed is horizontal
Let's find the time it takes for the kite to reach the ground
y = y₀ + v_{oy} t - ½ g t²
0 =y₀ + 0 -1/2 gt²
t = [tex]\sqrt{ \frac{2y_o}{g} }[/tex]
t = √(2 40/32)
t = 2.5 s
to find the horizontal velocity we must know the horizontal distance, let's use trigonometry
sin θ = y / l
θ = sin⁻¹1 y / l
θ = sin⁻¹ 40/50
θ = 53.1º
therefore the horizontal distance is
x = l cos 53.1
x = 50cos 53.1
x = 30 m
let's use the equation
x = v₀ₓ t
v₀ₓ = x / t
v₀ₓ = 30 / 2.5
v₀ₓ = 12 m / s
we look for the vertical component of the velocity
v_y = v_{oy} - g t
v_y = 0 - g t
v_y = - 9.8 2.5
v_y = -24.5 m / s
the negative sign indicates that the speed is directed downwards, because it is the arrival point, as they indicate that there is no friction, the exit speed is the same, worse with the opposite sign
We already have the two components of the velocity, let's use the Pythagorean theorem to find the modulus
v = [tex]\sqrt{v_x^2 + v_y^2}[/tex]
v = [tex]\sqrt{12^2 + 24.5^2}[/tex]
v = 27.28 m /s
we use trigonometry for the angle
tan θ = v_y / vₓ
θ = tan⁻¹ v_y / vₓ
θ = tan⁻¹ 24.5 / 12
θ = 63.9º
Match the following:
machinery part :nickel or chromium
ornamentation and decoration pieces :silver and gold
processed food :tin coated iron can
bridges and automobiles :zinc metal
distilled water:bad conductor
Answer:
iron metal :chromium
machinery part :nickel or chromium
ornamentation and decoration pieces :silver and gold
processed food :tin coated iron can
bridges and automobiles :zinc metal
distilled water:bad conductor
Explanation:
PLEASE ANSWER THIS WILL MARK AS BRAINLIEST PLEASE PUT TRUE ANSWERS
Charles Darwin developed the theroy of Natural Selection (Survival of the Fittest). Which statment below describes this concept?
A.
Animals with the best DNA will go extinct
B.
Organisms will adapt only to be able to have a food source
C.
Organisms that are only single cells will survive any environment
D.
Animals with the best genes and that have the ability to adapt will survive
Answer:
D
Explanation:
A is wrong bc best DNA will survive
B is wrong because organism adapt not only for food source but to be able to live in the environment as well
C is wrong because single celled organisms don't adapt
Which graph represents the relationship between the magnitude of the gravitational force exerted by earth on a spacecraft the distance between the center of the spacecraft the center of earth
Answer:
B as distance increase force decrease, but it is not a linear relationship.
One of alcohol's effects is to _____.
Answer:
slow down your reaction time
Explanation:
because alcohol makes nerve cells in the brain less excited and basically slows them down.
Suppose that white light strikes a flat piece of flint glass in air, coming in at an angle of 60 degrees to the surface (30 degrees from the normal or perpendicular). The index of refraction of this dense glass for red light is 1.710, for green light is 1.723, and for blue light is 1.735. What is the order of colors you would see in the refracted light inside the glass as they leave the surface
Answer:
The order of the light starting from the light closest to the normal line is
Blue light, followed by green ight and then lastly red light
Explanation:
White light travels from one medium to another such as from air to glass is refracted according to Snell's law as follows
n₁·sin(θ₁) = n₂·sin(θ₂)
The given parameters of the white light are;
The angle the incident (incoming) light makes with the surface = 90°
The angle of incidence of the light, θ₁ = 30°
The index of refraction of red light for the glass, n₂ = 1.710
The index of refraction of green light for the glass, n₃ = 1.723
The index of reaction of blue light for the glass, n₄ = 1.735
The refractive index of air, n₁ = 1
The angle of refraction of the red light, θ₂ is given as follows;
1 × sin(30°) = 1.710 × sin(θ₂)
sin(θ₂) = 1 × sin(30°)/1.710
θ₂ = sin⁻¹(1 × sin(30°)/1.710) ≈ 17°
The angle of refraction (to the surface's normal line) of the red light, θ₂ ≈ 17°
The angle of refraction of the green light, θ₃ is given as follows;
1 × sin(30°) = 1.723 × sin(θ₃)
sin(θ₃) = 1 × sin(30°)/1.723
θ₃ = sin⁻¹(1 × sin(30°)/1.723) ≈ 16.869°
The angle of refraction of the green light, θ₃ ≈ 16.869°
The angle of refraction of the green light, θ₄ is given as follows;
1 × sin(30°) = 1.723 × sin(θ₄)
sin(θ₄) = 1 × sin(30°)/1.735
θ₄ = sin⁻¹(1 × sin(30°)/1.735) ≈ 16.749°
The angle of refraction of the green light, θ₄ ≈ 16.749°
The order of colors we see as the in the refracted light inside the glass as the light leave the surface are;
The red light, with an angle of refraction of approximately 17° will be furthest from the normal
The green light which has an angle of refraction of 16.869° will follow and will be intermediate between the red and the blue light
The blue light which has an angle of refraction of 16.749° will follow next and it will be closest to the normal
The order of the light from the normal line will be blue, followed by green and then red light
· A wave with a frequency of 10 Hz and wavelength of 12m has what speed?
Which of the following solar phenomena is likely to have the most negative impact on Earth?
A solar flare as it may cause brief radio blackouts
An aurora as it may damage communication networks
An aurora as it may cause worldwide transmission problems
A solar flare as it may harm satellites and aircrafts flying near poles
Answer:
A solar flare as it may harm satellites and aircrafts flying near poles
Explanation:
Since solar flare is electro magnetic waves going to Earth the waves will mostly get absorbed by the north and south poles resulting in the aurora borealis, but if the solar flare is strong enough it may stop communications and engines in satellites and aircrafts and in result harming them
Answer:
A solar flare as it may harm satellites and aircrafts flying near poles
Explanation:
Activities:
1. Name the instrument that is used to measure Air Pressure.
2.Explain what is Cyclone and Anticyclone
Answer: barometer.
A cyclone is a storm or system of winds that rotates around a center of low atmospheric pressure. An anticyclone is a system of winds that rotates around a center of high atmospheric pressure.
What is the formula for Ba+2 and F-?
Answer:
BaF2
Explanation:
since you got the valence numbers just do the scissors move where you:
give the F the 2 and give the Ba the 1 so it be like
BaF2 here is the chemical compound
A scientist analyzes the light from a distant galaxy and finds that it is shifted to the longer wavelength of the electromagnetic spectrum. What does this data help to study?
1) the color of the galaxy
2) the distance of the galaxy from Earth
3) the existence of life on any planet in the galaxy
4) the study of the amount of light scattered by dust in space
Answer:
Option 2
Explanation:
As per the relation between the distance of the galaxy and shifting of the light of the galaxy towards any specific wavelength of the electromagnetic spectrum, a galaxy at great distance shifts more towards the red spectra that has the highest wavelength.
Thus, this observation give details about the distance of the galaxy from earth.
Answer:
b
Explanation:
Car X is travelling at 30m/s north. Its driver looks at car Y approaching on another road and he estimates it is moving at 15m/s south-west relative to his car. Calculate the velocity of car Y relative to the ground.
Answer: 22.1 m/s
Explanation:
The velocity of Car traveling 30 m/s towards the north
In vector form it is
[tex]v_x=30\hat{j}[/tex]
The velocity of car Y w.r.t X is
[tex]\Rightarrow v_{yx}=15[-\cos 45^{\circ}\hat{i}-\sin 45^{\circ}\hat{j}][/tex]
Solving this
[tex]\Rightarrow v_{yx}=v_y-v_x\\\Rightarrow v_y=v_{yx}+v_x[/tex]
putting values
[tex]\Rightarrow v_y=15[-\cos 45^{\circ}\hat{i}-\sin 45^{\circ}\hat{j}]+30\hat{j}[/tex]
[tex]\Rightarrow v_y=-10.606\hat{i}+19.39\hat{j}[/tex]
absolute velocity relative to ground is
[tex]\left | v_y\right |=\sqrt{(-10.606)^2+(19.39)^2}\\\left | v_y\right |=22.101\ m/s[/tex]
10 POINTSSS
My teacher said these are wrong and I'm confused. The blanks need filled.
All objects will remain at rest, or will continue to move at a constant speed in the same ______ unless acted upon by an unbalanced force. This property is called inertia.
Unbalanced forces cause an object to _______.
DONT PUT: VELOCITY, AND CHANGE IN MOTION.
Answer:
Direction & accelerate
Answer:
unbalanced forces cause an object to accelerate
HURRYYYYY, FASTTT, HELPPP What is the consequence of atoms being a singular closed system?
Atoms of a certain element contain a fixed amount of energy.
Atoms of a certain element can’t be altered by outside forces.
Atoms don’t interact with each other in any way.
Atoms decompose slowly over time as they lose energy.
1
Answer:
Atoms of a certain element contain a fixed amount of energy.
Explanation:
An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such defines the structure of a chemical element.
Generally, these atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.
Additionally, all the physical properties of a mineral result from the mineral's internal arrangement of atoms.
The consequence of atoms being a singular closed system is that atoms of a certain element contain a fixed amount of energy because the number of protons, neutrons and electrons are in a fixed proportion.
Suppose you are watching an ice-hockey game with some classmates. As the puck is sliding across the ice at a relatively constant speed, it passes close to a player, who hits it (with his stick) in the same direction as it is already moving. After the hit, you notice that the puck is moving much faster than it was before the hit. Your classmates propose the following three explanations for why the puck is moving faster after the hit than before. Whose reasoning do you agree with?
Student A: "The force of the stick was transferred to the puck during the hit. After the hit, the puck has more force, so it moves faster."
Student B: "The puck still has the force that started it moving, which is what keeps it moving at a constant speed. When the player hit it, he adds to this force, which makes the speed of the puck increase. After the hit, this extra force is gone, so the puck stops increasing its speed, but the original force is still there so now it moves at a faster constant speed."
Student C: "While the stick is in contact, it applies a force to the puck that makes its speed increase. As soon is contact is lost, this force disappears, so the speed of the puck stops increasing."
Answer:
the answer, the correct one is C
Explanation:
Let's propose the solution of this problem to know which explanation is correct, when the concha stick with the disc is an impulse exercise
I = ΔP
∫ F dt = pf-po
∫ F dt = m v_f - m v₀
Therefore, during the time that the contact lasts, a force is applied to the disk, which causes that if the amount of movement increases and therefore its speed increases, when the constant ceases the forces are reduced to zero and the disk no longer changes its momentum following with constant velocity.
When reviewing the answer, the correct one is C
Part D Here is one last question as a final check on your understanding of your work for this problem, looking at this problem as an example of the Conservation of Energy. The action in this problem begins at location A , with the block resting against the uncompressed spring. The action ends at location B, with the block moving up the ramp at a measured speed of 7.35 m/s . From A to B, what has been the work done by non-conservative forces, and what has been the change in the mechanical energy of the block-Earth system (the ramp is a part of the Earth)
Answer:
The answer is "39.95 J".
Explanation:
Please find the complete question in the attached file.
[tex]\to W_{AC}=(\mu \ m \ g \ \cos \theta ) d[/tex]
[tex]=(0.45 \times 1.60 \times 9.8 \times \cos 26^{\circ}) 6.30 \\\\=(7.056 \times \cos 26^{\circ}) 6.30 \\\\=6.34189079\times 6.30\\\\=39.95 \ J\\\\[/tex]
[tex]\therefore \\\\\bold{\Delta E =39.95 \ J}[/tex]
2.Test the age of your eyes. a.Hold a pencil or ballpoint pen vertically at arm's length. b.Close your left eye and focus on the tip. c.Quickly bring the pencil closer to your eye until it is out of focus. d.Have your partner measure the distance between your eye and the pencil. e.Repeat for both eyes. f.Try it with and without glasses (if you wear glasses). Age of your Eyes Cm91013185083
Answer:
See Explanation
Explanation:
Given
Steps: a - f
Table
[tex]\begin{array}{ccccccc}{cm} & {9} & {10} & {13} & {18} & {50} & {83} \ \\ {Age} & {10} & {20} & {30} & {40} & {50} & {60} \ \end{array}[/tex]
Note that: The question is a practical question and the result may differ base on individuals and environment.
So, I will pick up the question from how to determine the age of the eye after the distance between the eyes and the pencil has been established
In my case, the measurement is:
[tex]Length= 10.4[/tex]
Approximate
[tex]Length= 10[/tex]
From the above table, the corresponding age to 10cm is:
[tex]Age = 20cm[/tex]
If in your measurement, the length is approximately (for example):
[tex]Length = 9cm[/tex]
The age will be:
[tex]Age = 10[/tex]
A 0.55 kg projectile is launched from the edge of a cliff with an initial kinetic energy of 1550 J and at its highest point is 140 m above the launch point. (a) Calculate the horizontal component of its velocity. (b) Calculate the vertical component of its velocity just after launch. (c) At one instant during its flight the vertical component of its velocity is found to be 65 m/s. At that time, how far is it above or below the launch point
Answer:
a). 53.78 m/s
b) 52.38 m/s
c) -75.58 m
Explanation:
See attachment for calculation
In the c part, The negative distance is telling us that the project went below the lunch point.
You have a hand-crank generator with a 100-turn coil (each turn having an area of 0.0350 m2), which can spin through a uniform magnetic field that has a magnitude of 0.0500 T. You can turn the crank at a maximum rate of 3 turns per second, but the hand crank is connected to the coil through a set of gears that makes the coil spin at a rate 6 times larger than the rate at which you turn the crank. What is the maximum emf you can expect to get out of this generator
Answer:
Explanation:
Maximum emf produced = nωAB. where n is no of turns , A is area , B is magnetic field and ω is angular velocity .
n = 100 , A = .035 m²
B = .05 T
ω = 2π f , f is no of revolution per second by coil
= 2 x 3.14 x 6 x 3
= 113.04 rad /s
Maximum emf produced = 100 x 113.04 x .035 x .05
= 19.78 volt .
What affects the amount of rock that water can erode?
Speed
Time
Slope
All of the above
A 0.6 kg basketball is 3.0 high calculate its potential Energy PE=mgh
Jim and Sally both do identical jobs. Jim works quickly while Sally works slowly. Which of the following is true?
A) Sally uses more energy.
B) Jim uses more energy.
C) Jim uses more power.
D) Sally uses more power.
A blender has a power of 0.3 kW. It is used to make a fruit smoothie, which takes 50 seconds. How much energy is used? Give your answer in kilojoules.
Answer:
P=W/t
W=Pt=0.3kWx50s=15KJ
We have that the energy is used by a blender that has a power of 0.3 kW and which takes 50 seconds is
W=15KJ
From the question we are told
A blender has a power of 0.3 kW. It is used to make a fruit smoothie, which takes 50 seconds. How much energy is used? Give your answer in kilojoulesGenerally the equation for the Power is mathematically given as
P=W/t
Therefore
W=Pt
W=0.3*50
W=15KJ
Therefore
The energy is used by a blender that has a power of 0.3 kW and which takes 50 seconds is
W=15KJ
For more information on this visit
https://brainly.com/question/21811998
A square wave has amplitude 0 V for the low voltage and 4 V for the high voltage. Calculate the average voltage by integrating over one period of the waveform. Hint: the equation for a square wave will be a piecewise function and it will be convenient to start the integration where the voltage changes; for example in this problem we could define that during the first half of the period the voltage is 0 V and for the second half of the period the voltage is 4 V
Answer:
V_{average} = [tex]\frac{1}{2} V_o[/tex] , V_{average} = 2 V
Explanation:
he average or effective voltage of a wave is the value of the wave in a period
V_average = ∫ V dt
in this case the given volage is a square wave that can be described by the function
V (t) = [tex]\left \{ {{V=V_o \ \ \ t< \tau /2} \atop {V=0 \ \ \ \ t> \tau /2 } } \right.[/tex]
to substitute in the equation let us separate the into two pairs
V_average = [tex]\int\limits^{1/2}_0 {V_o} \, dt + \int\limits^1_{1/2} {0} \, dt[/tex]
V_average = [tex]V_o \ \int\limits^{1/2}_0 {} \, dt[/tex]
V_{average} = [tex]\frac{1}{2} V_o[/tex]
we evaluate V₀ = 4 V
V_{average} = 4 / 2)
V_{average} = 2 V
The Sun is divided into three regions.
True оr False?
Answer:
false I think
Explanation:
hope that help
so it's not divided in 3 regions
A hot air balloon is rising at a speed of 10 km/hr. One hour later, the balloon
is still rising at 10 km/hr. What is its acceleration?