Answer:
The speed with which the skier was going is approximately 2.9906 m/s
Explanation:
The given parameters are;
The distance the skier slides before coming to rest, s = 12.4 m
The coefficient of friction between the skier and the snow, [tex]\mu _k[/tex] = 0.0368
Therefore, for conservation of energy, we have;
Initial kinetic energy = Work done by the kinetic friction force
Initial kinetic energy = 1/2·m·v²
The work done by the kinetic friction force = [tex]\mu _k[/tex]×m×g×s
Where;
m = The mass of the skier
v = The speed with which the skier was going
g = The acceleration due to gravity = 9.8 m/s²
s = The distance the skier slides before coming to rest = 12.4 m
[tex]\mu _k[/tex] = The kinematic friction = 0.0368
Therefore, for conservation of energy, we have;
1/2·m·v² = [tex]\mu _k[/tex]×m×g×s
1/2·v² = [tex]\mu _k[/tex]×g×s
v² = 2×[tex]\mu _k[/tex]×g×s = 2 × 0.0368 × 9.8 × 12.4 = 8.943872
v = √(8.943872) ≈ 2.99063070271 ≈ 2.9906 m/s
The speed with which the skier was going = v ≈ 2.9906 m/s.
A monkey pushes a rock horizontally on a frictionless table with a net force of 10 N for 2.0 m. How much kinetic energy does the rock gain?
Round the answer to two significant digits
Answer:
The answer is 20J
Explanation:
How much power must an engine have to lift a 10,000 kg safe at a constant velocity to a 26 m height in 5 seconds?
Answer:
520kw or 520, 000w
Explanation:
Given that power equsls workdone /time taken
P=mgh
____
t
M=10, 000kg
h=26m
T=5sec
g=10m/s²
Recall:
P=mgh/t
P=10,000×10×26/5
P=20,000×26
P=520,000w or 520kw
what caused the rate of the erosion to change around 1905 and 1906
Answer:
What caused the slope to change around 1905 and 1906? Building the Canadian hydroelectric plant reduced the rate of erosion after 1906. This change in the rate of erosion is represented by the change in the slope on the graph. Hydroelectric dams convert kinetic energy from moving water to electrical energy.
Answer:
In 1906, around the time the Canadian hydroelectric plant began operating, the erosion rate decreased to approximately 0.7 meters per year.
Explanation:
Item 1 Circuit A has a resistance of 7.5 ohms, and circuit B has a resistance of 5 ohms. Which statement about the circuits must be correct? (1 point) Item 2 Item 3 If the current in circuit A is less than the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B. Item 4 If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B. If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B. If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B. 0 Type here to search е c
Answer:
e4atetetsgts4tgesetse
Explanation:
ger54ttagcuit B, then the voltage in circuit A is less than the voltage in circuit B. Item 4 If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B. If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B. If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B. 0 Type here to search е c
Electric field lines can never cross. What would crossed electric field lines indicate?
a field pointing in two directions
an attractive force on a charge
a nonuniform area of the field
a place where the field strength is zero
Answer:
It indicates that a force has 2 directions at the point at which they cross
Answer:
A. A field pointing in two directions
A pendulum consists of a 2.0 kg stone swinging on a4.0 m string of negligible mass. The stone has a speed of 8.0 m/swhen it passes its lowest point. (a) What is the speed when thestring is at 60# to the vertical? (b) What is the greatest angle withthe vertical that the string will
Answer:
a) [tex]v_{60^{o}} =4.98 m/s[/tex]
b) [tex]\theta_{max}=79.34^{o}[/tex]
Explanation:
This problem can be solved by doing an energy analysis on the given situation. So the very first thing we can do in order to solve this is to draw a diagram of the situation. (see attached picture)
So, in an energy analysis, basically you will always have the same amount of energy in any position of the pendulum. (This is in ideal conditions) So in this case:
[tex]K_{lowest}+U_{lowest}=K_{60^{o}}+U_{60^{0}}[/tex]
where K is the kinetic energy and U is the potential energy.
We know the potential energy at the lowest of its trajectory will be zero because it will have a relative height of zero. So the equation simplifies to:
[tex]K_{lowest}=K_{60^{o}}+U_{60^{0}}[/tex]
So now, we can substitute the respective equations for kinetic and potential energy so we get:
[tex]\frac{1}{2}mv_{lowest}^{2}=\frac{1}{2}mv_{60^{o}}^{2}+mgh_{60^{o}}[/tex]
we can divide both sides of the equation into the mass of the pendulum so we get:
[tex]\frac{1}{2}v_{lowest}^{2}=\frac{1}{2}v_{60^{o}}^{2}+gh_{60^{o}}[/tex]
and we can multiply both sides of the equation by 2 to get:
[tex]v_{lowest}^{2}=v_{60^{o}}^{2}+2gh_{60^{o}}[/tex]
so we can solve this for [tex]v_{60^{o}}[/tex]. So we get:
[tex]v_{60^{o}}=\sqrt{v_{lowest}^{2}-2gh_{60^{0}}}[/tex]
so we just need to find the height of the stone when the pendulum is at a 60 degree angle from the vertical. We can do this with the cos function. First, we find the vertical distance from the axis of the pendulum to the height of the stone when the angle is 60°. We will call this distance y. So:
[tex]cos \theta = \frac{y}{4m}[/tex]
so we solve for y to get:
[tex]y = 4cos \theta[/tex]
so we substitute the angle to get:
y=4cos 60°
y=2 m
so now we can find the height of the stone when the angle is 60°
[tex]h_{60^{o}}=4m-2m[/tex]
[tex]h_{60^{o}}=2m [/tex]
So now we can substitute the data in the velocity equation we got before:
[tex]v_{60^{o}}=\sqrt{v_{lowest}^{2}-2gh_{60^{0}}}[/tex]
[tex]v_{60^{o}} = \sqrt{(8 m/s)^{2}-2(9.81 m/s^{2})(2m)}[/tex]
so
[tex]v_{60^{o}}=4.98 m/s [/tex]
b) For part b, we can do an energy analysis again to figure out what the height of the stone is at its maximum height, so we get.
[tex]K_{lowest}+U_{lowest}=K_{max}+U_{max}[/tex]
In this case, we know that [tex]U_{lowest}[/tex] will be zero and [tex]K_{max}[/tex] will be zero as well since at the maximum point, the velocity will be zero.
So this simplifies our equation.
[tex]K_{lowest} =U_{max}[/tex]
And now we substitute for the respective kinetic energy and potential energy equations.
[tex]\frac{1}{2}mv_{lowest}^{2}=mgh_{max}[/tex]
again, we can divide both sides of the equation into the mass, so we get:
[tex]\frac{1}{2}v_{lowest}^{2}=gh_{max}[/tex]
and solve for the height:
[tex]h_{max}=\frac{v_{lowest}^{2}}{2g}[/tex]
and substitute:
[tex]h_{max}=\frac{(8m/s)^{2}}{2(9.81 m/s^{2})}[/tex]
to get:
[tex]h_{max}=3.26m[/tex]
This way we can find the distance between the axis and the maximum height to determine the angle of the pendulum about the vertical.
y=4-3.26 = 0.74m
next, we can use the cos function to find the max angle with the vertical.
[tex]cos \theta_{max}= \frac{0.74}{4}[/tex]
[tex]\theta_{max}=cos^{-1}(\frac{0.74}{4})[/tex]
so we get:
[tex]\theta_{max}=79.34^{o}[/tex]
The speed when the string is at 60 degrees to the vertical is approximately 8.85 m/s. The greatest angle with the vertical that the string will make is approximately 57.6 degrees.
(a) To find the speed when the string is at 60 degrees to the vertical, we can apply the conservation of mechanical energy between the lowest point (initial position) and the 60 degrees point (final position).
At the lowest point, all of the gravitational potential energy is converted into kinetic energy:
m × g × h = (1/2) × m × v²
v = √(2 × g × h) = √(2 × 9.8 × 4.0) ≈ 8.85 m/s.
Therefore, the speed when the string is at 60 degrees to the vertical is approximately 8.85 m/s.
(b) The greatest angle with the vertical that the string will make, we need to determine the maximum height reached by the stone. At the highest point, all of the kinetic energy is converted into gravitational potential energy:
(1/2) × m × v² = m × g h(max)
h(max) = (v²) / (2 × g) = (8.0²) / (2 × 9.8) ≈ 3.27 m.
Using the sine function:
sin(Θ) = h(max) / 4.0,
Θ = sin⁻¹(h(max) / 4.0) ≈ sin⁻¹(3.27 / 4.0) ≈ 57.6 degrees.
Therefore, the greatest angle with the vertical that the string will make is approximately 57.6 degrees.
To know more about potential energy:
https://brainly.com/question/24284560
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HELP I'M LAZY AND D U M B
(please use information from the small text to answer the questions)
1. What do the curved blue lines wrapping around Earth represent?
2. The geomagnetic poles move over time. What causes this to happen?
3. How do Earth's geomagnetic poles differ from its geomagnetic poles?
4. Mars has a week magnetic field. How do you think the conditions on the surface of Mars compare with those on Earth? What would that mean for astronauts traveling to Mars in the future?
Maps can convey a lot of different types of information. They can tell you where you are or they can tell you something about a location. Earth scientists often use maps that have coordinates so that they can locate themselves or the features they are interested in. Different types of maps show different things well. For example, some types of maps show the tropical areas really well but do a terrible job depicting the polar regions.
Can you hear this Picture???
If you know it, you get it
Answer:
Ah yes.. Beetlejuice
Explanation:
I hear it so well ngl
“Energy is never created of destroyed, it only transforms from one form to another” is the definition of…
A. The Law of Diminishing Returns
B. The Law of Conservation of Energy
C. The Law of Universal Gravitation
D. The Law of Entropy
Answer:
it is B. The Law of Conservation of Energy
Explanation:
hope this helps
Roller coasters accelerates from initial speed of 6.0 M/S2 final speed of 70 M/S over four seconds. What is the acceleration?
Answer:
[tex]a=16\ m/s^2[/tex]
Explanation:
Motion With Constant Acceleration
It's a type of motion in which the velocity of an object changes uniformly in time.
The formula to calculate the change of velocities is:
[tex]v_f=v_o+at[/tex]
Where:
a = acceleration
vo = initial speed
vf = final speed
t = time
The roller coaster moves from vo=6 m/s to vf=70 m/s in t=4 seconds. To calculate the acceleration, solve for a:
[tex]\displaystyle a=\frac{v_f-v_o}{t}[/tex]
[tex]\displaystyle a=\frac{70-6}{4}=\frac{64}{4}[/tex]
[tex]\boxed{a=16\ m/s^2}[/tex]
1. The resultant force on a ball is not zero. What will happen to the ball? *
(1 Point)
It will move or change direction.
O it will remain stationary.
O it will spin on its axis.
Answer:
it will more and change direction
Explanation:
because the resultant force (R) is not equal zero so may be there is a force greater than the other one and the ball will more in the direction of greater force.
and it can't be remain stationary because R=! 0 .
How do scientists classify species?
A. By comparing the ages of individuals
B. By comparing common names
C. By comparing who discovered them
D. By comparing traits
Answer:
D. By comparing traits
Explanation:
Because age isn't genetic, as well as names, as well as who discovered, but traits are genetic.
Answer:
D
Explanation:
Everyone experiences a wide range of emotions, but when could they indicate a mental disorder?
Answer:
Excessive paranoia, worry, or anxiety.
Long-lasting sadness or irritability.
Extreme changes in moods.
Social withdrawal.
Dramatic changes in eating or sleeping patter
Explanation:
hope it helps brainliest if right thx :)
The car has a mass of 22,000Kg. Calculate the force needed to stop the car.
Answer:
Momentum of car = 1200 kg * 10 m/s = 12000 kgm/s Momentum = Force * time 12000 kgm/s = Force * 20s Force = 600 N
Explanation:
the diameter of the moon is _____ that of the earth
answers:
2/3
1/4
1/2
1/3
Answer:
2,158.8 mi?
Explanation:
sorry if this is wrong
Atom X has an atomic number of 10. Atom Y has an atomic number of 4. All of these statements about atoms X and Y are correct except
A . atom X has 8 valence electrons
B. atom Y is less reactive than atom X
C. atom Y has 2 valence electrons
D atom X has the same number of energy levels as atom Y
An LDR was placed near a light source. The following results were
recorded: potential difference = 5.50V current = 12.5 mA. Which equation
links current, potential difference and resistance? *
Answer:
V = 440I
Explanation:
According to ohm's law which states that the current passing through a metallic conductor at constant temperature is directly proportional to the potential difference across its ends.
Let V be the potential difference
I is the current
R is the resistance
Mathematically;
V∝I
V = IR
Given
Potential difference V = 5.50Volts
Current = 12.5mA = 12.5*10^-3A
Current I = 0.0125A
Recall that V = IR
R = V/I
Substitute the given parameters into the formula;
R = 5.50/0.0125
R = 440 ohms
Hence the equation that links current, potential difference and resistance is expressed as;
V = I(440)
V = 440I
A ______ measurement that both size and direction may be represented by an arrow
Answer:
Vector
Explanat
Vector is the only right answer in the situatuin
Weight is the direct result of :
A. Distance
B. The amount of gravity being pulled
What is most likely to happen during deposition?
Answer:
a person appears at a specified time and place and gives sworn testimony
Explanation:
Hope this helps
An object on Earth's surface has a mass of 18.7 kg. The object's weight is ________ N.
Answer:
The mass of an object is the same on Earth, in orbit, or on the surface of the Moon. ... the absence of air resistance, all objects fall with the same acceleration g. ... A 1.0-kg mass thus has a weight of 9.8 N on Earth and only about 1.7 N ... What force does he apply if the stone accelerates at a rate of 1.5m/s2?
Explanation:
Microwaves travel at the speed of light, 300,000 km/s. What is the wavelength of a microwave received at 1000 gigahertz?
Answer:
3 x 10⁻⁴m
Explanation:
Given parameters:
Speed of light = 300000km/s
Frequency = 1000gigahz = 1000 x 10⁹Hz
Unknown:
Wavelength = ?
Solution:
To solve this problem, we use the expression below:
V = F ∧
V is the speed
F is the frequency
∧ is the wavelength
300000 = 1000 x 10⁹ x ∧
Wavelength = 3 x 10⁻⁷km = 3 x 10⁻⁴m
Mass varies depending on where the object is located.
True or false
Which statement describes the heat that results from the radioactive decay of elements deep in the Earth's interior?
Answer:
Try C as the answer, if it works do the thanks button! :D
Explanation:
C) It drives the convection currents in the mantle.
The radioactive decay of elements in the Earth's mantle and crust results in production of daughter isotopes and release of neutrinos and heat energy.The radioactive decay in Earth's crust and mantle continuously adds heat and slows the cooling of the Earth.The heat from radioactive decay is thought to be distributed in the crust and mantle layers of the planet, greatly influencing currents in the mantle.Learn more:
brainly.com/question/23976097
in an effort to reach the store before it closed the motorist increase the speed of his car from 20 m per second to 60 meters per second over a four second. What was the car's acceleration
Answer:
10
Explanation:
Givens
vi = 20 m/s
vf = 60 m/s
t = 4 second.
Formula
a = (vf - vi) / t
a = (60 - 20)/4
a = 40 / 4
a = 10 m/s^2
SOMEONE HELP PLEASE ASAP ITS TIMED
A boy is slowly pushing a box across the floor. In which direction is friction occurring?
a. away from the boy
b. toward the boy
c. up
d. down
Pangaea was not the first, nor will it be the last, super continent. In the process of continental drift, sometimes chunks of continents disappear. Describe how this can happen.
Answer:
Explanation:
there could be earthquakes or the tectonic plates under can make it fall apart, natural disasters
hope this helps!!
A book is resting on the table. Forces are exerted _____.
upward by the table
downward by the book
in equal and opposite directions
all of the above
Answer:
downward by the book
Explanation:
because of gravity
slader How much energy is required to move a 1040 kg object from the Earth's surface to an altitude four times the Earth's radius
Answer:
ΔU = 5.21 × 10^(10) J
Explanation:
We are given;
Mass of object; m = 1040 kg
To solve this, we will use the formula for potential energy which is;
U = -GMm/r
But we are told we want to move the object from the Earth's surface to an altitude four times the Earth's radius.
Thus;
ΔU = -GMm((1/r_f) - (1/r_i))
Where;
M is mass of earth = 5.98 × 10^(24) kg
r_f is final radius
r_i is initial radius
G is gravitational constant = 6.67 × 10^(-11) N.m²/kg²
Since, it's moving to altitude four times the Earth's radius, it means that;
r_i = R_e
r_f = R_e + 4R_e = 5R_e
Where R_e is radius of earth = 6371 × 10³ m
Thus;
ΔU = -6.67 × 10^(-11) × 5.98 × 10^(24)
× 1040((1/(5 × 6371 × 10³)) - (1/(6371 × 10³))
ΔU = 5.21 × 10^(10) J
Fred spends most Sunday afternoons watching pro football games and consuming large quantities of
food. What effect does this practice have upon his inertia? Explain.
I
Answer:
His inertia increases.
Explanation:
Inertia is defined as the force which keeps stationary objects to stay still (remain at rest) or moving objects in motion at the same speed and in the same direction unless it is stopped by an external force. It can also be defined as the resistance of an object to resist change by remaining in its state of rest or in motion. Therefore, his inertia increases.