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
Zolol [24]
3 years ago
13

An elevator supported by a single cable descends a shaft at a constant speed. The only forces acting on the elevator are the ten

sion in the cable and the gravity. Which one of the following statements is correct? Group of answer choices
A. The work done by the gravity is zero joules.
B. The tension force does positive work.
C. The net work done by the two forces is zero joules.
D. The work done by the tension force is zero joules.
E. The gravitational force does negative work.
Physics
1 answer:
VikaD [51]3 years ago
3 0

Answer:

C. The net work done by the two forces is zero joules.

Explanation:

Work (W) is defined as the product of force F) by the distance (d)the body travels due to this force.  

W= F*d Formula ( 1)

The work is positive (W+) if the force has the same direction of movement of the object.  

The work is negative (W-) if the force has the opposite direction of the movement of the object.

The component of the force that performs work must be parallel to the displacement.  

Calculation of the forces

We apply Newton's second law:

∑F = m*a

∑F : algebraic sum of the forces in Newton (N)

m : mass in kilograms (kg)

a : acceleration in meters over second square (m/s²)

∑F = m*a  

a = 0 because the elevator moves at constant speed.

∑F=0

T-W = 0

T = W  

Calculation of work done by the forces

W₁ :  work done by the gravity= (+ W*d ) J

W₂ : work done by the tension force=( -T*d) J

Net work done by the two forces(W₁-W₂):

W₁= W₂ .because T = W  

W₁-W₂ =0

You might be interested in
Steve and Carl are driving from Scranton to Bridgeport a distance of 180 miles if they're speed averages 60 miles an hour how lo
Anarel [89]
It will take at least 3 hours for them to get to Bridgeport
7 0
3 years ago
The number ocean waves that pass a buoy in one second is _ of the wave
mr_godi [17]
The number of ocean waves that pass a buoy in one second is the frequency of the <span>wave. The crest of a transverse wave is its highest point. </span>
7 0
3 years ago
Read 2 more answers
Ultraviolet light from a distant star is traveling at 3.0 × 108 m/s. how long will it take for the light to reach earth if it mu
castortr0y [4]

Given speed and the distance that must be covered, the time it will take the ultraviolet light to reach the earth is 3.7 × 10⁴ hours.

<h3>What is Speed?</h3>

Speed is simply referred to as distance traveled per unit time.

Mathematically, Speed = Distance ÷ time.

Given the data in the question;

  • Speed of the Ultraviolet light c = 3.0 × 10⁸m/s = 1.08 × 10⁹km/h
  • Distance it must cover d = 4.0 × 10¹³km
  • Time elapsed t = ?

We substitute our given values into the expression above.

Speed = Distance ÷ time

1.08 × 10⁹km/h = 4.0 × 10¹³km ÷ t

t = 4.0 × 10¹³km ÷ 1.08 × 10⁹km/h

t = 3.7 × 10⁴ hrs

Therefore, given speed and the distance that must be covered, the time it will take the ultraviolet light to reach the earth is 3.7 × 10⁴ hours.

Learn more about speed here: brainly.com/question/7359669

#SPJ4

5 0
2 years ago
using mass and distance, identify and compare the sun's and moon's contribution to the formation of tides on earth
vekshin1

Answer:

Based on its mass, the sun's gravitational attraction to the Earth is more than 177 times greater than that of the moon to the Earth.

7 0
3 years ago
Help plzzzzzzzzzzzzzzzz!
aksik [14]
 

concave <span>ray diagrams were constructed in order to determine the general location, size, orientation, and type of image formed by concave mirrors. Perhaps you noticed that there is a definite relationship between the image characteristics and the location where an object placed in front of a concave mirror. but, convex</span><span>ray diagrams were constructed in order to determine the location, size, orientation, and type of image formed by concave mirrors. The ray diagram constructed earlier for a convex mirror revealed that the image of the object was virtual, upright, reduced in size and located behind the mirror. </span>
3 0
3 years ago
Other questions:
  • How do you calculate the work done when lifting an object?
    7·1 answer
  • Part II # 1 A mass on a string of unknown length oscillates as a pendulum with a period of 4 sec. What is the period if: (Parts
    10·1 answer
  • Which statements about the moon’s phases are true? Check all that apply.
    12·2 answers
  • A projectile is launched from ground level at angle u and speed v0 into a headwind that causes a constant horizontal acceleratio
    12·1 answer
  • Two difference between far point and near point​
    9·1 answer
  • How can a systematic error affect the reported data?
    13·2 answers
  • What is the magnification when an object is placed at 2f from the pole of the convex mirror? 
    15·1 answer
  • The value of g is greater at the poles than at the equator why​
    14·2 answers
  • Imagine that you are sitting on a couch watching TV and that you will continue sitting on the couch watching TV until someone ch
    8·1 answer
  • Here is the picture of an aircraft, with the forces working on it shown. Identify the force that corresponds to the question mar
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!