Một ô tô khối lượng một tấn chuyển động nhanh dần đều trên một đường bằng, hệ số ma sát giữa bánh xe và mặt đường là 0,1. Lực kéo của động cơ ô tô bằng 1200 N. Lấy g = 10 m/s2. Thời gian cần thiết để ô tô đạt được tốc độ 36 km/h từ trạng thái nghỉ là bao nhiêu?
A diagram is drawn showing a swing set with a swing pulled backward prior to release. The diagram shows how the swing will move forward and then backward after it is initially released. At which point in the diagram is all of the energy gravitational potential energy?
A) as the released swing begins moving backward
B) at the highest point as the swing moves forward
C) when the swing is pulled back prior to release
D) just after release of the swing
Answer:C) When the swing is pulled back to prior release
Explanation:
This question involves the concepts of the law of conservation of energy, gravitational potential energy, and kinetic energy.
All of the energy is gravitational potential energy at "C) when the swing is pulled back prior to release".
The law of conservation of energy states that at any point the total energy of the swing must be constant, which means:
Total Energy = Gravitational Potential Energy + Kinetic Energy = Constant
It is clear that the swing has a non-zero speed in all given situations except the situation in part C), where the swing is at rest before release. Since the kinetic energy exists due to motion in the object. Hence, the kinetic energy will be zero when the swing is pulled back prior to release. It means all the energy in the swing at this time will be the gravitational potential energy.
Learn more about the law of conservation of energy here:
brainly.com/question/20971995?referrer=searchResults
The attached picture explains the law of conservation of energy.
Once you start pulling your object with less force than friction, what should you expect your object to do? What about when your object is pulled with more force than friction?
#Case -1
If Pulling force is less than frictional force the object won't move .
#Case-2
If Pulling force is greater than frictional force then object will be .
In order to calculate friction force you need Limiting friction first .
[tex]\\ \sf\longmapsto F_L=\mu sN[/tex]
u s is coefficient of static friction and N is normal reactionOr
[tex]\\ \sf\longmapsto F_L=\mu smg[/tex]
A 10-kg box is being pulled across the table to the right at a constant speed with a force of 50N, directed 30 degrees below the horizontal.
a.) Calculate the force of friction acting on the box.
b.) Calculate the normal force acting on the box.
Answer:
Explanation:
Assuming the table is horizontal
As speed is constant, friction must exactly balance the horizontal component of the applied force
Ff = 50cos30 = 43 N
The normal force must oppose both the weight of the box and the vertical component of the applied force.
N = 10(9.8) + 50sin30 = 123 N
The frictional force can be calculated with the angle and mass of the moving body and the normal force acting on it. The normal force on the body is 98 N and the frictional force is 7.712 N.
What is friction?Friction is the resistance to the movement of a body. If the motion is in a frictionless path then the body will moves in a constant speed in a straight line.
The normal force is the product of mass of the body and gravity 9.8. Then the frictional force can be calculated by the equation with of friction as follows:
Frictional force = F × cos ∅
is the angle.
Thus frictional force = 50N × cos 30
= 7.712 N
The normal force F = m × g
= 10 Kg × 9.8 m/s²
= 98 N.
Therefore, the normal force acting on the body moving with a constant speed and constant force 50 N and horizontal angle 30 degree is 98 N and the frictional force is 7.712 N.
To find more about friction, refer the link below:
https://brainly.com/question/28356847
#SPJ2
When Beakman pushes Liza back of the swing he is storing _____ energy.
A. stopped
B. moving
C. potential
D. kinetic
what is meant by cathode rays?
what is radio activity and state three of it's effects?
1cathode rays plural : the high-speed electrons emitted in a stream from the heated cathode of a vacuum tube
2: a stream of electrons emitted from the cathode of a vacuum tube —usually used in plural
At the instant shown in Figure 3, the blocks are moving toward each other with the same speed of 0.35 m/s. The blocks collide 0.50 seconds later. What is the speed of the two=block system's center of mass just before the blocks collide?
Answer:
The blocks c
Explanation:
The distance between tow objects is increased by 3 times the original distance. How will this change the force of attraction between the two objects?
Answer:
force of attraction will be increased by 9
Explanation:
force of attraction is inversely proportional to square of distance
i.e F= 1/R²
F=1/3R²
F=1/9R
multiply both side by 99×F= 9×1/9R
9F= 1/R
so force of attraction is 9 times
A snowboarder drops from rest into a halfpipe of radius R and slides down its frictionless surface to the bottom
(a) Show that the snowboarder's speed at the bottom of the halfpipe is
v = 2gR (use conservation of energy)
(b) Show that the snowboarder's centripetal acceleration at the bottom is
ac = 2g (Apply the expression for centripetal acceleration)
(c) Show that the normal force on the snowboarder at the bottom of the halfpipe has a magnitude of 3mg (Use Newton's second law of motion)
A snowboarder drops from rest into a halfpipe of radius R and slides down its frictionless surface to the bottom, the snowboarder's speed is [tex]\mathbf{v = \sqrt{2gR}}[/tex]
The snowboarder's centripetal acceleration at the bottom is [tex]\mathbf{a_c = 2g}[/tex]. The normal force acting on the snowboarder at the bottom of the halfpipe = 3mg
According to the conservation of energy, at any given point of motion, the energy of a system will always be constant.
Using the conservation of energy at rest and also at the bottom of the pipe.
Total potential energy of the person(since its at rest = Total kinetic energy at the bottom of the pipe.[tex]\mathbf{mgR = \dfrac{1}{2}mv^2}[/tex]
The objective is to make the velocity (v) the subject of the formula:
[tex]\mathbf{gR = \dfrac{1}{2}v^2}[/tex]
[tex]\mathbf{2gR = v^2}[/tex]
[tex]\mathbf{v = \sqrt{2gR}}[/tex]
(b)
Using the expression for centripetal acceleration;
[tex]\mathbf{a_c = \dfrac{v^2}{R}}[/tex]
here,
let's replace [tex]\mathbf{v \ \ \ with \ \ \sqrt{2gR}}[/tex];
Then;
[tex]\mathbf{a_c = \dfrac{(\sqrt{2gR})^2}{R}}[/tex]
[tex]\mathbf{a_c =2g}[/tex]
From the image attached below;
Provided that:
n = normal forcew = mg weight of the person[tex]\mathbf{F_c}[/tex] = centripetal forceThen, we can infer that the normal net force acting on the person can be computed as:
[tex]\mathbf{F_c = n -mg}[/tex]By rearrangement;
[tex]\mathbf{n =F_c +mg}[/tex]where;
[tex]\mathbf{F_c = 2 mg}[/tex]∴
n = 2mg + mgn = 3mg
Therefore, we can conclude that the snowboarder's speed, centripetal force, and normal force are proved.
Learn more about centripetal force here:
https://brainly.com/question/11324711?referrer=searchResults
2
Ca
+
O
2
→
2
CaO
What is the product of the reaction
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
The product in a chemical reaction is written on the Right side of the arrow, so
the product formed here in given reaction is :
CaO (Calcium Oxide)A 10 kg box initially at rest accelerates uniformly to a speed of 20 m/s in 2 seconds. Determine the A. energy gained by the block, B. Power developed by the box at the end of 10 seconds.
Answer:
20 40
Explanation:
A 10 kg box initially at rest accelerates uniformly to a speed of 20 m/s in 2 seconds, energy gained by the block 2000 J and Power developed by the box at the end of 10 seconds 5000 Watt
What is work done?The total amount of energy transferred when a force is applied to move an object through some distance
The work done is the multiplication of applied force with displacement.
Work Done = Force * Displacement
As given in the problem A 10 kg box initially at rest accelerates uniformly to a speed of 20 m/s in 2 seconds
By using the first equation of motion
v = u + at
20 = 0 + 2a
a = 10 m/s²
By using the third equation of motion
v² - u² = 2as
20² - 0² = 2×10×s
s = 400/20
s = 20 m
Force = ma
= 10 ×10
= 100 N
work done = Force × displacement
= 100 ×20
= 2000 J
Velocity after 10 seconds
V= u + at
= 0 + 10×10
= 100 m/s
work done after 10 seconds
= 1/2mv²
= 0.5×10×10²
=50000 J
Power = work done / time
= 50000/10
= 5000 Watt
Thus, energy gained by the block 2000 J and Power developed by the box at the end of 10 seconds 5000 Watt
Learn more about work done here
brainly.com/question/13662169
#SPJ2
For an experiment to produce useful data, what must happen?
A. It must be performed by a famous scientist.
B. It must prove a hypothesis correct.
C. It must be published in a famous journal.
D. It must be repeated several times.
Answer: D
Explanation: It must be repeated several times. (You could have different results everytime. Kind of like a dice. If you only roll it once and get a 3, you will only think it rolls a 3 unless you roll it and get different results or unless you've seen a dice before.)
A car moving at 8.5 m/s crashes into a tree and stops in 0.32 s. Calculate the magnitude of the force, in newtons, the seatbelts exerts on a passenger in the car to bring him to a halt. The mass of the passenger is 66.5kg.
Answer:
Explanation:
I=Q2- Q1
And I = F. (t2-t1)
t = 0,32s
v = 8,5 m/s
Q = m.v
Q=66,5.8,5 = 565,25 kg.m/s
F. (t2-t1) = 565,25
F.0,32 = 565,25
F = 1766,4 N
A device that absorbs and draws heat from a hot object, dispersing it into the
surroundings, is which one of the following?
A. Heat sink
B. Piston
C. Heat engine
D. Internal combustion engine
Answer:
A. Heat sink
Explanation:
what happens to the cereal underneath the clear container when it's near a wool?
Answer:
they can't breath and they gon dead
Explanation:
yum yum yum yum yum
Answer:
the answer is in my mind but not coming in the mouth I'll tell you when I remember ''sorry ''
you hit a ball with a bat. the ball acts on the bat, and the bat exerts equal and opposite force on the ball. This will cause the ball to be in (equilibrium or acceleration). Explain your answer.
Answer:
equilibrium because its equal force on the ball.
Explanation:
Answer:
good
Explanation:
Several lawmakers argue that constructing coal plants is a necessity. Which statement describes scientific evidence people can use to disagree with the lawmakers’ claim?
Burning fossil fuels increases greenhouse gas emissions.
Coal mining creates many kinds of jobs.
Energy production rates are the highest with the use of coal plants.
Forests are destroyed as storage facilities for electricity are constructed.
Answer:
Burning fossil fuels increases greenhouse gas emissions.
When Beakman lets go of Liza and she starts moving her stored _____ changed into ____ energy.
A. moving / stopped
B. potential / kinetic
C. stopped / moving
D. kinetic / potential
An airplane travels 2400 km at a speed of 600 km/h, decreases its speed to 400 km/h for the next 1200 km and travels the last 2,500 km at a speed of 500 km/h.
Problem 1, Question 1: What is the total travel time?
Total time:
Problem 1, Question 2: Find the average speed of the plane for the trip.
Average speed:
help :D
how is the ionization, E, related to a period of elements?
Answer:
2 Answers. Ionization energies increase across a Period, and decrease down a Group.
Explanation:
Answer:
The ionization energy of an element increases as one moves across a period in the periodic table.
Explanation:
The electrons are held tighter by the higher effective nuclear charge.
Describe a real life situation in which you have experienced Newtons First Law. Use the words “unbalanced force” and “inertia” in your answer
Plz help
Answer: Options that describes first law of motion from the question are;
An overall net force must be applied to an object before it can move.
Newton’s first law of motion is also known as the law of inertia.
Newton’s first law applies to an object whether it is moving or not.
Newton's first law states can be regarded as law of inertia. it made us to understand that when a body is resting then it keeps the rest unless there is external force been acted on it or if the body is moving at a constant speed, it will continue until there is external force acted.
A body will move from its resting only when net force is applied.
Example of this law is seen in when someone is sitting in a car putting on the seat belt.
This law applies to moving object as well as static object.
Therefore, option B,C and E right.
Explanation:
Answer: I would say like if a person jumps out of a moving vehicle, he falls forward due to inertia of motion. One example of Newton's first law in real life is, when you are walking with a glass filled with water, you will notice that the water spills at certain locations when you walk at faster pace.
Explanation:
Two balls were dropped at the same time from the top of a ladder. The balls are of equal size but ball A has more mass than Ball B. Which best describes the time it would take for the two balls to hit the ground
A .Not enough information
B. Ball B would hit the ground first
C. Ball A and B will hit the ground at the same time.
Answer:
A
Explanation:
If we ignore air resistance or friction, the balls would hit the ground at the same time. The question does not state whether or not there is air resistance.
If there was air resistance, ball A would hit the ground first.
Again, there is no information provided on whether is is air resistance or not, so there is not enough information.
While on her concert tour in the US, my Austrian friend Andrea brought along a small electric
fabric-steamer. The steamer draws a current of 4.2 A on a 220 V line in Austria. If she plugged it
into an electrical line in the US, where the household voltage is 110 V, how much current would
the steamer draw? How well do you think it will perform?
Answer:
A battery connected to a 140 resistor dissipates 17W of power. If the circuit contains only the battery and the resistor, what is the voltage of the battery?
Explanation:
ra body of mass x is raised to a height of 2m above the ground what it's potential energy if the body is allowed to fall what is it's kinetic energy when half way down
Answer:
Explanation:
PE = mgh = 2xg
Half way down, half of the potential energy will have been converted.
KE = xg
If a person paddles a canoe up a creek, a distance of 13.09 km, how fast does she need to move in order to get to the end of the creek within 2.371 hours?
Answer:
Below
Explanation:
To find the velocity of the person you can use this formula
velocity = displacement / time
velocity = 13.09 km / 2.371 hours
velocity = 5.5208 km/h
= 5.521 km/h
Hope this helps!
4word puzzle about sounds waves down
what are the similarities between standard units and non-standard units?
Standard units of measurement are units of measurement that are typically used within each measurement system, such as inches, feet, ounces, pounds, kilograms, or cups. ... Nonstandard units of measurement are units of measurement that aren't typically used, such as a pencil, an arm, a toothpick, or a shoe.
What is represented in this picture? (50 points and brainliest for the correct answer!!!!)
Answer:
I don't know
Explanation:
Please give me Brainliest answer
Answer:
PRESSURE ???
Explain the
difference between an
oxygen atom and a carbon atom
Answer:
Carbon atoms are made up of 6 protons, 6 electrons, and 6 neutrons, whereas Oxygen atoms are made of 8 protons, 8 neutrons, and 8 electrons.
Explanation:
This may not sound like a big difference at the atomic level, but it is responsible for all of the differences between Oxygen and Carbon.
Help!!!!!!!!!!!!!!!!
Answer:
_Sorrrrry_ I can't help u_