1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Anna [14]
4 years ago
8

Using the scientific definition of work, does moving an object a greater amount of distance always require a greater amount of w

ork? Why or why not?

Physics
1 answer:
tester [92]4 years ago
3 0
The answer is no. If you are dealing with a conservative force and the object begins and ends at the same potential then the work is zero, regardless of the distance travelled. This can be shown using the work-energy theorem which states that the work done by a force is equal to the change in kinetic energy of the object.
W=KEf−KEi
An example of this would be a mass moving on a frictionless curved track under the force of gravity.
The work done by the force of gravity in moving the objects in both case A and B is the same (=0, since the object begins and ends with zero velocity) but the object travels a much greater distance in case B, even though the force is constant in both cases.

You might be interested in
A race car starting from rest accelerates uniformly at a rate of 4.90 meters per squared. What is the cars speed after it has tr
shusha [124]
Ok, we need to find a relation for the speed as it relates to the acceleration.  This is given by the integral of acceleration:

v= \int\limits^{t}_{0} {a} \, dt' =at

Where we have the initial velocity is 0m/s and a will be 4.90m/s².

But we see there is an issue now... We know the velocity as a function of time, but we don't know how long the car has been accelerating!  We need to calculate this time by now finding the position function as a function of time.  This way we can solve for the time, t, that it takes to go 200m accelerating this way and then substitute that time into our velocity equation and get the velocity. 
Position is just the integral of velocity:

s= \int\limits^{}_{} {at} \, dt = \frac{1}{2}at^2

Where the initial velocity and initial position are both zero.

Now we set this position function equal to 200m and find the time, t, it took to get there

\frac{1}{2}(a \frac{m}{s^2} )t^2=200m \\  \\ \frac{1}{2}4.90 \frac{m}{s^2} t^2=200m \\  \\ t^2= \frac{400m}{4.90 \frac{m}{s^2}}=81.63s^2 \\  \\ t= \sqrt{81.63s^2 }  =9.04s

Now let's put t=9.04s into our velocity equation:

v =at=4.9\frac{m}{s^2} \times 9.04s=44.3 \frac{m}{s}


8 0
3 years ago
When riding a 10-speed bicycle up a hill, a cyclist shifts the chain to a larger-diameter gear attached to the back wheel. Why i
dimaraw [331]

To solve this problem we will use the concepts of the moment of rotational inertia, angular acceleration and the expression of angular velocity.

The rotational inertia is expressed as follows:

I = \sum mr^2

Here,

m = Mass of the object

r = Distance from the rotational axis

The rotational acceleration in terms of translational acceleration is

\alpha = \frac{a}{R}

Here,

a = Acceleration

R = Radius of the circular path of the object

The expression for the rotational speed of the object is

\omega = \frac{\Delta \theta}{\Delta t}

Here,

\Delta \theta is the angular displacement of the object

The explanation by which when climbing a mountain uphill is changed to a larger pinion, is because it produces a greater torque but it is necessary to make more pedaling to be able to travel the same distance. Basically every turn results in less rotations of the rear wheel. Said energy that was previously used to move the rotation of the wheel is now distributed in more turns of the pedal. Therefore option a and c are correct.

This would indicate that the correct option is D.

8 0
4 years ago
5. Which of these affect the brightness of a bulb? Choose all that apply.* 6 po
schepotkina [342]

Answer:

The voltage of the battery

7 0
3 years ago
Which one the answer to this question
tangare [24]
The second bubble is the answer:)
4 0
3 years ago
Un hamster esta sentado sobre un tocadisco cuya rapidez angular es constante si el hamster se mueve a un punto localizado al dob
kotegsom [21]

Answer:

b) se duplica

Explanation:

The disk is moving with constant angular velocity, let's call it \omega.

The linear velocity of a point on the disk is given by

v=\omega r

where r is the distance of the point from the axis of rotation.

In this problem, the object is moved at a distance twice as far as the initial point, so

r' = 2r

Therefore, the new linear velocity is

v'=\omega r' = \omega (2r) = 2 \omega r = 2 v

So, the velocity has doubled, and the correct answer is

b) se duplica

8 0
3 years ago
Other questions:
  • Which condition is necessary for a standing wave?
    10·2 answers
  • If the particles are oxygen ions carrying a charge of −2e and the magnetic field magnitude is 0.12 T , how long does it take eac
    6·1 answer
  • Scientific models can be used for a variety of different purposes. Which of the following is not a possible use for a scientific
    7·2 answers
  • Five renewable energy resources are wind, sunlight, moving water and geothermal energy.
    11·2 answers
  • If the distance d (in meters) traveled by an object in time t (in seconds) is given by the formula d=a+bt2, the si units of a an
    5·1 answer
  • which of the following is not true about warming up a: warming up what's the heart rate increase gradually b: warming up increas
    7·1 answer
  • An object experiences an acceleration of 7.7 m/s^2. As a result, it accelerates from rest to 20 m/s. How much distance did it tr
    5·2 answers
  • How much energy is transferred in 10 seconds with a current of 13 amperes and a potential difference of 230 volts?​
    7·1 answer
  • An ultrasound machine is being used to try to identify potential kidney stones. The machine is working properly and no kidney st
    11·2 answers
  • A blinking light of constant period is situated on a lab cart. Which diagram best represents a photograph of light, taken every
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!