Answer:gravity
Explanation:
As Sonja coasts down the hill on her bike, the gravitational potential energy is converted into kinetic energy, which is the energy that increases her speed as she moves downhill.
When Sonja freewheels down the hill on her bike, the primary energy transfer is the conversion of gravitational potential energy to kinetic energy. At the top of the hill, the bike has a certain amount of potential energy due to its elevated position. As she moves downhill, this potential energy is converted into kinetic energy, which is the energy of motion, allowing the bike to increase in speed.
If we were not to ignore friction and air resistance, these factors would cause some of the kinetic energy to transform into thermal energy, due to the friction between the bike tires and the road as well as the air resistance against the rider and the bike.
However, since the question asks us to ignore these factors, we focus solely on the transformation of gravitational potential energy into kinetic energy as Sonja coasts down the hill.
Helppp me please !!
Answer:
the frequency of this light is [tex]1.5\,\,10^{16}[/tex] Hz (which coincides with the fourth option listed among possible answers)
Explanation:
Recall the relationship between wavelength and frequency of radiation based upon the speed of light in vacuum:
[tex]frequency\,*\,wavelength\,=\, speed\,\,of\,light\\frequency\,*\,wavelength\,=\,3\,\,10^8\,\frac{m}{s} \\frequency\,*\,20 \,\,10^{-9}\,m\,=\,3\,\,10^8\,\frac{m}{s}\\frequency\, =\,\frac{3\,\,10^8}{2\,\,10^{-9}} \,\frac{1}{s} \\frequency\,=1.5\,\,10^{16}\,\,Hz[/tex]
In the process shown above, we have written the speed of light in meters per second, and also converted the 20 nano-meters into meters, in order to reduce SI units properly and have the result shown in units of 1/second (that is hertz's - abbreviate "Hz")
In what way is a projectile (a ball thrown horizontally for example) using constant velocity motion?
Can someone please answer this?
Pleaseeeee❗️❗️❗️❗️
Answer:
The horizontal component of the velocity is always constant in accordance with the Newton's first law of motion since there is no other force acting in the horizontal direction.
Explanation:
A ball moving in projectile motion is under a variable resultant velocity on the object but the horizontal component of the velocity is always constant in accordance with the Newton's first law of motion since there is no other force acting in the horizontal direction. While a projectile motion the body is always under the influence of gravity and so its vertical component of velocity varies continuously. During the analysis of such a problem we always break the velocity components of the body for our ease of evaluation using the equations of motion.What are the top three osha cited ladder violations
Answer: not having a portable ladder extend 3 feet above the landing
improper use of the top of step ladders
lack of work or training
Explanation: career safe online
The top three OSHA cited ladder violations are improper maintenance, improper use, and missing fall protection systems, endangering worker safety.
These violations are common because they relate to fundamental ladder safety. Maintaining a ladder's condition is crucial to ensure it's safe for use. Inadequate ladder use includes actions that increase the risk of falls, such as reaching too far or using a ladder not designed for the task.
Missing fall protection is a serious violation, especially when working at heights where a fall could lead to severe injuries or fatalities. Employers must ensure proper ladder training, maintenance, and use, and provide the necessary safety equipment to protect workers from fall hazards. Violations in these areas can result in OSHA citations and penalties.
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What is the distance traveled between 0 s and 30 s?
Answer:
0m
Explanation:
In physics this is 0m, why?
Okay so, you moved 60 meters (in position/m) the first 10 seconds (sec) and then between 10 and 15 seconds, you took a brake and didn't move. (The graph is still because the time is constant and your motion is 0 meters).
When 15 seconds have passed, you go back where you were, exactly at 0 meters, your initial position.
In reality would this be 60 meters + 60 meters back which would be 120 meters, or 0.12km if you will. But in physics world, it's 0 meters in position.
Hope you understood!
Good luck!
Astrophysicist Dr. D
Answer:
120 m
Explanation:
The displacement from 0 s to 30 s is 0 m, since the change in position between those points is 0 m. However, we are asked to find the distance traveled, not the displacement.
The object travels 60 m forward, then 60 m backward. So the total distance traveled is 120 m.
Rodney is trying out one of Santa's new games that consists of three pieces that blow apart if the wrong key is inserted into the door. The elf picks the wrong key and the board explodes. One piece of mass 2 kg goes off at an angle of 60° from the horizon at 10 m/s. A second piece of mass 1.2 kg travels at an angle of 180° and is moving at 15 m/s.
a) find the momentum of the third piece.
b) find the velocity of the third piece if it's mass is 3 kg.
a) The momentum of the third piece is 19.1 kg m/s
b) The velocity is 6.4 m/s at an angle of [tex]-65^{\circ}[/tex]
Explanation:
a)
We can solve this problem by applying the law of conservation of momentum in 2D. In fact, the total momentum of the board before the explosion must be equal to the total momentum of the 3 pieces after the explosion.
Before the explosion, the total momentum is zero, since the board is at rest. Resolving into the x- and y- components, this means that the two components of the momentum are zero:
[tex]p_x = 0\\p_y = 0[/tex]
After the explosion, we have:
[tex]p_x = (2 kg)(10 m/s)( cos 60^{\circ}) + (1.2 kg)(15 m/s)(cos 180^{\circ})+p_{3x}[/tex]
where [tex]p_{3x}[/tex] is the x-component of the momemtum of the 3rd piece. By solving,
[tex]p_x = -8+p_{3x}[/tex]
And since the x-momentum must be conserved,
[tex]0=-8+p_{3x} \rightarrow p_{3x}=8 kg m/s[/tex]
Similarly, along the y-axis,
[tex]p_y = (2 kg)(10 m/s)( sin 60^{\circ}) + (1.2 kg)(15 m/s)(sin 180^{\circ})+p_{3y}[/tex]
where [tex]p_{3y}[/tex] is the y-component of the momemtum of the 3rd piece. By solving,
[tex]p_y = 17.3+p_{3y}[/tex]
And since the y-momentum must be conserved,
[tex]0=17.3+p_{3y} \rightarrow p_{3y}=-17.3 kg m/s[/tex]
So now we can find the momentum of the third piece:
[tex]p_3 = \sqrt{p_{3x}^2+p_{3y}^2}=\sqrt{8^2+(-17.3)^2}=19.1 kg m/s[/tex]
b)
The momentum of the third piece is given by
[tex]p_3 = m v_3[/tex]
where
m = 3 kg is the mass of the piece
[tex]v_3[/tex] is the velocity
Solving for [tex]v_3[/tex], we find
[tex]v_3 = \frac{p_3}{m}=\frac{19.1}{3}=6.4 m/s[/tex]
We can also find the direction, which is identical to the direction of the momentum, by using the following equation:
[tex]\theta = tan^{-1}(\frac{p_{3y}}{p_{3x}})=tan^{-1}(\frac{-17.3}{8})=-65^{\circ}[/tex]
So, the third piece flies off at 6.4 m/s at an angle of [tex]-65^{\circ}[/tex].
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NEED ANSWER NOW PLZ!!
Carbon-14 undergoes radioactive decay in the reaction above. Determine the type of radiation emitted in this reaction and describe what is happening to the nucleus during this reaction.
A) Alpha radiation is emitted in this equation because the atomic number increases (from 6 to 7). This means a helium atom has been emitted from the nucleus.
B) Beta radiation is emitted in this equation because the atomic number increases (from 6 to 7). This means a neutron has decayed into a proton, which occurs by emitting an electron.
C) Beta radiation is emitted in this equation because the atomic number increases (from 6 to 7). This means a neutron has decayed into a electron, which occurs by emitting an proton.
D) Gamma radiation is emitted in this equation because the atomic number increases (from 6 to 7). This means a neutron has decayed into a proton, which occurs by emitting an electron.
OPTION B
Emission of beta radiation is what's occurring in the radioactive decay of Carbon-14. This is due to a neutron decaying into a proton and giving off an electron (beta particle), causing the atomic number to increment from 6 to 7.
Explanation:In the case of Carbon-14 undergoing radioactive decay, the correct answer would be B) Beta radiation is emitted because the atomic number increases (from 6 to 7). This increase indicates that a neutron in the nucleus of Carbon-14 has decayed into a proton. This decay process emits an electron, known as a beta particle, and this is what gives this type of radioactive decay its name: beta decay. The emission of this beta particle is what causes the atomic number to increase (as the atomic number is simply the number of protons in the nucleus), and thus transforms the Carbon-14 nucleus into a Nitrogen-14 nucleus.
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1. An object is moving in a straight line at constant speed. Which of the following is true?
There are no forces acting on the object.
The object has 0 acceleration.
The object has constant velocity.
a. I only
b. ll only
c. II and III only
d. I, II, and III
c. II and III only (the object has 0 acceleration and the object has constant velocity.)
Why?
Let's discard each of the given options to find the correct one(s).
- There are no forces acting on the object:False, if an object has a constant speed, it does not mean that there are no forces acting on it, in fact, there will be always acting forces, like frictional force, gravity force, air resistance, and others.
- The object has a 0 acceleration:True, in an object is moving at constant speed, it means that there is no acceleration, the speed will be the same all the time during motion.
- The object has constant velocity:True, if an object is moving in a straight line at constant speed the velocity will be also constant. The velocity of an object is referring to its speed and its direction, if the object is moving in a straight line, the direction will be the same, so, if the speed is constant, the velocity will be also constant.
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Analyze the following terms and phrases about solar activity. Select the two that represent correct matches between cause and effect.(1 point)
a) solar activity -- sudden eruptions of large bubbles of plasma and magnetic energy
b) coronal mass ejection -- relatively cool spot on surface of the sun
c) sun's magnetic field -- uneven churning of the sun's gravitational field
d) solar flare -- sudden release of magnetic energy
e) sunspot -- magnetic field of the sun emerges as a loop
Answer:
a) solar activity -- sudden eruptions of large bubbles of plasma and magnetic energy
and
d) solar flare -- sudden release of magnetic energy
Explanation:
We can start by eliminating the options that are definitely wrong.
A coronal mass ejection is not a relatively cool spot on surface of the sun, in fact such a spot is a sunspot, while a coronal mass ejection occurs when the magnetic field of the sun emerges as a loop. Thus, both options B and E are incorrect, leaving only A, C, and D. Option C makes no sense, as the sun's gravitational field does not 'churn'. Thus, only options A and D are left. A closer look at A and D reveals they are correct; solar flares are in fact sudden releases of magnetic energy, as seen in this quote from UC Berkeley's website; "Solar flares are caused by sudden changes of strong magnetic fields in the Sun's corona.". And solar activity is a blanket term for the effects of eruptions of plasma and magnetic energy from the sun.
Can somebody match the following please I need to pass this class
Answer:
Explanation:
B)2) Statosphere
E) 5) Exosphere
A) 1) Troposphere
C)3) Mesosphere
D) 4) Thermosphere
When force is applied to an object, what happens
Answer:
The force on he object can cause an object to move or speed up. It can also make it stop or change direction.
Explanation:
John traveled East at 10 m/s for ten
seconds. He realized he had gone too
far and made a U-turn. He traveled
West at 5 m/s for six seconds. Calculate
John's displacement.
a. 30 m
b. 70 m
C. 100 m
d. 130 m
Answer:
Option D
130 m
Explanation:
From the concept of speed, distance=speed*time
When traveling East, displacement=10*10=100 m (since he takes 10 seconds while traveling at a speed of 10 m/s)
When traveling West, displacement=5*6=30 m (since John takes 6 seconds to travel at a speed of 5 m/s)
Total displacement=Displacement East+ Displacement West=100+30=130 m
calculate the magnitude of impulse applied to a 0.75 kilogram cart to change its velocity from 0.50 meters per second east to 2.00 meters per second east
Answer:
1.125 N s towards East
Explanation:
since both velocities are in same direction hence change in velocity is
Δ V = final - initial
= 2.00 - 0.50
= 1.50 towards East
impulse = change of linear momentum
= mass × change in velocity
= 0.75 ×1.50
= 1.125 N s towards East
You push a book sitting on a desk with a force of 5 N, but the book does not move. What is the static friction?
Answer:
The static friction is 5 N acting in the direction opposite to that of the force of push.
Explanation:
Given:
A book lying on a table. Force of push is 5N.
Now, the book is not moving. This clearly means that some resistive force is acting in the opposite direction which has the same magnitude as that of the applied force, thus making the net force acting on the book equal to zero.
This resistive force acting in the opposite direction is called the static frictional force.
Therefore, the static friction acting on the book is equal to 5 N and acts in the direction opposite to that of the force of push.
Factors that influence Wellness
Answer:
Physical and mental factors, work, and lifestyle
Explanation:
I'm kind of taking a guess at this, but I'd assume these factors affect and influence personal wellness
Answer the question please
Answer:
B. solubility I think lmk if its wrong
Letti is having a problem in her experiment that she does not know how to solve. In order to move forward, Letti needs to be .
Answer:
In order to move forward, Letti needs to be creative.
Explanation:
Creative:
A person is said to be creative if that person has ability to think out of the box.
For example: if a person having a problem and instead of using traditional methods of solving the problem then that person thinks about news ideas then that person is creative,
As in our case, letti can use problem solving technique to find a solution of her problem.
Creative Problem technique:
It is such a problem solving method in which we use unconventional ways to get the solution of a problem. We analyze the problems with news view points so that we can reach at innovative ideas of solutions.
Answer: creative
Explanation: i just took the test
Which statements accurately differentiate between dark matter and dark energy? Select the two correct answers.
a)Dark energy is the cause of the acceleration of the universe, while dark matter is the cause of the formation of structures.
b) There is much more dark matter in the universe, by mass.
c) Dark matter is the cause of the acceleration of the universe, while dark energy is the cause of the formation of structures.
d) Dark matter is black, while dark energy cannot be seen.
e) There is much more dark energy in the universe, by mass.
Answer:
a) Dark energy is the cause of the acceleration of the universe, while dark matter is the cause of the formation of structures.
e) There is much more dark energy in the universe, by mass.
Explanation:
Dark energy rises as an explanation of the accelerated expansion of the Universe, since it was expected that this slow down since The Big Bang, as a consequence of the gravitational attraction between the different objects (galaxies, planets, etc) but instead, the observations show how it is accelerating.
Dark matter in the other hand was born to explain why stars that were more farther for the supermassive black hole in the center of the Milky way galaxy didn't decrease their rotational velocity as it was expected.
[tex]v = \sqrt{\frac{G M}{r}}[/tex]
Where v is the rotational velocity, G is the gravitational constant, M is the mass inside the orbital radius, and r is the orbital radius.
If the distance increases the orbital speed decreases (inversely proportional).
Answer:a and e
Explanation:
please help me i dont get it
The answers are:
39:
a - 1 mile
b - 0 miles
40:
[tex]a=-4\frac{m}{s^{2} }[/tex]
41:
[tex]Displacement=3.60 miles\\Distance=5 miles[/tex]
Why?
Solving 39:
To answer the questions, we need to remember that distance and displacement are different things. Distance refers to the total "ground" covered during motion, while displacement refers to how far is the object/body from its starting point.
So,
39:
a - the total distance traveled corresponds to the length of the track which is 1 mile.
b - The displacement is equal to 0 because they finished at the starting point, the distance between the starting and the finishing point is equal to 0.
40:
We can solve the problem using one of the given equations:
[tex]a=\frac{v_f-v_i}{t}[/tex]
Since we know all the information, we just need to substitute it into the equation:
[tex]a=\frac{v_f-v_i}{t}\\\\a=\frac{2\frac{m}{s} -16\frac{m}{s} }{3.5s}=\frac{-14\frac{m}{s} }{3.5s}\\\\a=-4\frac{m}{s^{2} }[/tex]
So, the car's acceleration was -4m/s2 (the car was reducing its speed)
41:
We can solve the problem using one of the given equations (Pythagorean Theorem):
[tex]c^{2}=a^{2}+b^{2}[/tex]
[tex]Displacement=\sqrt{(3mi(North))^{2}+(2miles(East))^{2}}\\\\Displacement=\sqrt{9+4}=\sqrt{13mi^{2}}=3.60miles[/tex]
The distance will be:
[tex]Distance=3mi+2mi=5miles[/tex]
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In which example would the amount of work done equal
zero?
A. holding a 1,000-N rock overhead Hope this helps :)
Saul is in Germany, driving on the
Autobahn. He drives 50 km in fifteen
minutes. How fast is Saul driving?
a. 50 km/h
b. 100 km/h
c. 200 km/h
d. 400 km/h
Answer: c
Explanation:Use equation for speed: V=S/t
S=50 km -distance
t=15 min=0.25h -time
V=?
------------------------
V=S/t
V=50km/0.25h
V=200km/h
Two substances were mixed and there was a color change and small flames. What can you infer happened?
A physical property was observed
A chemical change occurred
A change in state from solid to liquid
Matter was destroyed
A chemical change occurred
Explanation:
There are two types of changes, physical changes and chemical changes:
A chemical change occurs when the nature of a substance changes, and new substances are formed. This occurs when the bonds between molecules in the reactants break, and they re-form into new substance. A change in the colors of the substance involved is, for example, a sign that a chemical change occurredA physical change occurs when there is a change in state of a substance, but no new substances are formed. For instance, a physical change is the melting of ice, or the boiling of water, or the condensation of water..In this problem, two substances are mixed and there is a color change and small flames. The color change indicates the formation of new substances, so a chemical change has occurred. Moreover, the presence of small flames indicates that a chemical reaction has occurred (burning of oxygen), so a new substance has formed, so this is another indication of a chemical change.
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What type of power plant burns material to make electricity?
Answer:
A fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator.
Explanation:
A dog, that has a mass of 16 kgs, runs across a yard. What is the average force applied to the dog from the ground as it runs across the yard?
Answer:
156.96 N
Explanation:
F=ma where m is the mass and a is acceleration
Substituting 16 Kg for m and 9.81 m/s2 for g then
F=16*9.81= 156.96 N
13. Bari kicked a ball and its leaves the ground at an angle 30° with a velocity of 20 m/s.
Find hang time of the ball
11 Pari Iricked a ball and its leaves the ground at an angle 30° with a velocity of 20. m/s.
I have a physics test upcoming and I’m particularly stuck on this question and I would be grateful if anyone could help me out.
Answer:
The hang time is 2.04 seconds
Explanation:
2-D Motion
It referred to as a situation where an object is launched in such a way it describes a curve, reaches a top height and then returns to ground level after traveling a certain distance x away from the launch point.
Let [tex]v_o[/tex] be the launching speed forming an angle [tex]\theta[/tex] with the horizontal reference. The hang time (time the object remains in the air) is given by
[tex]\displaystyle t_h=\frac{2V_{oy}}{g}[/tex]
Since
[tex]\displaystyle v_{oy}=v_o\ sin\theta[/tex]
Then
[tex]\displaystyle t_h=\frac{2v_o\ sin\theta }{g}[/tex]
We'll use the given values
[tex]\displaystyle v_o=20\ m/s\ ,\ \theta =30^o[/tex]
[tex]\displaystyle t_h=\frac{2(20)sin30^o}{9,8}[/tex]
[tex]\displaystyle t_h=2.04\ sec[/tex]
The hang time is 2.04 seconds
EL. A white ball with mass 143 g is moving at a velocity of 7.9 m/s.
CS
It collides with a red ball with mass of 150 g.
The red ball is stationary before the collision. The white ball stops after the collision.
Calculate the velocity of the red ball after the collision.
Give your answer to two significant figures.
Answer:
[tex]\displaystyle v_2'=7.5\ m/s[/tex]
Explanation:
Conservation Of Linear Momentum
The total momentum of both balls won't change regardless of their interaction while no external forces are acting on the system. We'll use the following variables m1,m2,v1,v2,v1',v2' for the mass of the white ball, the mass of the red ball, their velocities before the collision, and their velocities after the collision, respectively .
The provided data is as follows:
[tex]\displaystyle m_1=143\ gr=0.143\ kg[/tex]
[tex]\displaystyle v_1=7.9\ m/s[/tex]
[tex]\displaystyle m_2=150\ gr=0.15\ kg[/tex]
[tex]\displaystyle v_2=0[/tex]
[tex]\displaystyle v_1'=0[/tex]
To preserve the total linear momentum, the following equation must stand
[tex]\displaystyle m_1\ v_1+m_2\ v_2=m_1\ v_1'+m_2\ v_2'[/tex]
Solving for [tex]v_2'[/tex]
[tex]\displaystyle v_2'=\frac{m_1\ v_1+m_2\ v_2-m_1\ v_1'}{m_2}[/tex]
[tex]\displaystyle v_2'=\frac{0.143(7.9)+0-0}{0.15}[/tex]
The final speed of the red ball is
[tex]\boxed{\displaystyle v_2'=7.5\ m/s}[/tex]
Final answer:
The final velocity of the red ball after the collision, calculated using conservation of momentum, is approximately 1.13 m/s to two significant figures.
Explanation:
Using the principles of conservation of momentum, we can solve for the final velocity of the red ball after the collision. The formula for conservation of linear momentum in a two-object system is m1v1 + m2v2 = m1v1' + m2v2', where m represents mass, v represents initial velocity, and v' represents final velocity. Since the white ball (m1 = 143 g) stops after the collision, its final velocity is 0 m/s. The red ball (m2 = 150 g) is initially stationary, so v2 = 0 m/s. From the data given, we can set up the equation as follows:
143 g × 7.9 m/s + 150 g × 0 m/s = 143 g × 0 m/s + 150 g × v2'
Solving for v2' (the final velocity of the red ball), we get v2' = (143 g × 7.9 m/s) / 150 g. Converting grams to kilograms to use SI units, we calculate:
v2' = (0.143 kg × 7.9 m/s) / 0.150 kg
v2' = 1.13 m/s.
The velocity of the red ball after the collision is approximately 1.13 m/s to two significant figures.
What an object at rest stays at rest and an object in motion with the same speed and in the same direction unless acted upon by an unbalanced force is newton's 1st law of motion?
True
Or
False
Answer:
True.
Explanation:
Newton's First Law of Motion states that every object continues in it's state of rest or of uniform motion in a straight line unless acted upon by an external force.
What is the kinetic energy of a 50-kg child running to catch the school bus at
2 m/s?
O A. J
O B. 25 J
O C. 100J
O D. 200
Answer:
Option C
100 J
Explanation:
Kinetic energy, KE is given by
[tex]KE=0.5mv^{2}[/tex] where m is the mass and v is the velocity
Substituting 50 Kg for mass, m and 2 m/s for velocity v then we obtain
[tex]KE=0.5*50*2^{2}=100 J[/tex]
Therefore, the child's kinetic energy is equivalent to 100 J
Answer:100J
Explanation:
Help Meeeeee
Two kids are roller skating. Amy, with a mass of 55 kg, is traveling forward at 3 m/s. Jenny, who has a mass of 40 kg, is traveling in the opposite direction at 5 m/s. They crash into each other and hold onto each other so that they move as one mass. How fast are they traveling?
Answer:
0.4 m/s
Explanation:
From the law of conservation of momentum, the sum of initial momentum equals the sum of final momentum
Momentum, p=mv where m is the mass and v is the velocity
[tex]m_1v_1+m_2v_2=(m_1+m_2)v_c[/tex] where [tex]v_c[/tex] is the common velocity, [tex]v_1[/tex] and [tex]v_2[/tex] are velocities of Amy and Jenny respectively, [tex]m_1[/tex] and [tex]m_2[/tex] are masses of Amy and Jenny respectively.
Taking forward direction as positive, opposite direction is negative hence [tex]v_1[/tex] is 3 m/s while [tex]v_2=-5 m/s[/tex]
[tex]55 kg\times 3 m/s +(40 kg\times -5 m/s)=(55 kg+40 kg)v_c[/tex]
[tex]95 kg v_c=-35 kg.m/s[/tex]
[tex]v_c=\frac {-35}{95}=-0.368421053 m/s\approx -0.4 m/s[/tex]
Therefore, they travel at 0.4 m/s in the direction of Jenny's movement
sound is heard louder in newly furnished room ,why?
A girl pushes a 10.0kg sled at a constant speed by applying a force of 75N at an angle of 30 degrees with respect to the horizontal. The sled is pushed over a distance of 15 meters. How much work is done by the force of friction?
Answer
given,
mass of sled = 10 Kg
Force applied by girl = ?
angle of inclination = 30°
distance = 15 m
Sled is moving with constant speed hence acceleration will be equal to zero.
now,
F - mg sin θ - f = m a
F - mg sin θ - f = 0
F - mg sin θ = f
where f is the frictional force acting opposite to the applied force
mg sin θ is the component of the weight which is opposing the motion of the sled
now,
f = F - mg sin θ
f = 75 - 10 x 9.8 x sin 30°
f = 26 N
now,
Work done = f. s cos ∅
where ∅ is the angle between frictional force and displacement which is equal to 180°
W= 26 x 15 x cos 180°
W = -390 J
work done by frictional force is equal to W = -390 J
The work done by child to move the system is 974.25 Joules.
The work done is given by an expression shown below,
[tex]Workdone=Force*Distance*Cos\theta[/tex]
Where [tex]\theta[/tex] angle between force and direction of displacement.
Given that, [tex]Force=75N,Distance=15m,\theta=30[/tex]
Substitute in above expression.
[tex]Workdone=75*15*cos(30)\\ \\ Workdone=75*15*0.866\\ \\ Workdone=974.25Joule[/tex]
Hence, the work done by child to move the system is [tex]974.25[/tex] Joules.
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