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
sesenic [268]
3 years ago
14

A factory worker pushes a 32.0 kg crate a distance of 7.0 m along a level floor at constant velocity by pushing horizontally on

it. The coefficient of kinetic friction between the crate and floor is 0.26.
Required:
a. What magnitude of force must the worker apply?
b. How much work is done on the crate by this force?
c. How much work is done on the crate by friction?
d. How much work is done on the crate by the normal force? By gravity?
e. What is the total work done on the crate?
Physics
1 answer:
g100num [7]3 years ago
6 0

Answer:

(a) 81.54 N

(b) 570.75 J

(c) - 570.75 J

(d) 0 J, 0 J

(e) 0 J  

Explanation:

mass of crate, m = 32 kg

distance, s = 7 m

coefficient of friction = 0.26

(a) As it is moving with constant velocity so the force applied is equal to the friction force.

F = 0.26 x m x g = 0.26 x 32 x 9.8 = 81.54 N

(b) The work done on the crate

W = F x s = 81.54 x 7 = 570.75 J

(c) Work done by the friction

W' = - W = - 570.75 J

(d) Work done by the normal force

W'' = m g cos 90 = 0 J

Work done by the gravity

Wg = m g cos 90 = 0 J

(e) The total work done is

Wnet = W + W' + W'' + Wg = 570.75 - 570.75 + 0 = 0 J  

You might be interested in
Two objects of the same size are both perfect blackbodies. One has a temperature of 3000 K, so its frequency of maximum emission
bija089 [108]

Answer:

a) The colder body (3000k), b) hearter body c) 12000K body

Explanation:

This exercise should know the power emitted by the objects and the distribution of this emission in the energy spectrum, for this we will use Stefan's laws and that of Wien's displacement

Stefan's Law                     P = σ A e T⁴

Wien displacement law   λ T = 2,898 10⁻³ m K

Let's calculate the power emitted for each object.

As they are perfect black bodies e = 1, they also indicate that they have the same area

T = 3000K

       P₁ = σ A T₁⁴

T = 12000K

       P₂ = σ A T₂⁴

       P₂ / P₁ = T₂⁴ / T₁⁴

       P₂ / P₁ = (12000/3000)⁴

       P₂ / P₁ = 256

This indicates that the hottest body emission is 256 times the coldest body emission.

Let's calculate the maximum emission wavelength

Body 1

T = 3000K

       λ T = 2,898 10-3

       λ₁ = 2.89810-3 / T

       λ₁ = 2,898 10-3 / 3000

       λ₁ = 0.966 10-6 m

      λ₁ = 966 nm

T = 12000K

      λ₂ = 2,898 10-3 / 12000

      λ₂ = 0.2415 10-6 m

      λ₂ = 214 nm

a) The colder body (3000k) emits more light in the infrared, since the emission of the hot body is at a minimum (emission tail)

b) The two bodies have emission in this region, the body of 3000K in the part of rise of the emission and the body to 12000K in the descent of the emission even when this body emits 256 times more than the other, so this body should have the highest broadcast in this area

c) The emission of the hottest 12000K body is mainly in UV

d) The hottest body emits more energy in UV and visible

e) No body has greater emission in all zones

5 0
3 years ago
Which of the following terms refer to the area immediately around the crime?
UkoKoshka [18]

Answer:

A....It is a crime sene

Explanation:

6 0
3 years ago
Read 2 more answers
A horizontal force of magnitude 46.3 n pushes a block of mass 4.14 kg across a floor where the coefficient of kinetic friction i
IrinaVladis [17]
A) Calling F the intensity of the horizontal force and d the displacement of the block across the floor, the work done by the horizontal force is equal to
W=Fd = (46.3 N)(4.25 m)=196.8 J

b) The work done by the frictional force against the motion of the block is equal to:
W_f =  -F_f d =- (\mu mg) d =-(0.609)(4.14 kg)(9.81 m/s^2)(4.25 m)=
=-105.1 J
Part of these 105.1 Joules of work becomes increase of thermal energy of the block (\Delta E_B), and part of it becomes increase of thermal energy of the floor (\Delta E_F). We already know the increase in thermal energy of the block (38.2 J), so we can find the increase in thermal energy of the floor:
\Delta E_F = 105.1 J - \Delta E_B = 105.1 J-38.2 J=66.9 J

c) The net work done on the block is the work done by the horizontal force F minus the work done by the frictional force (the frictional force acts against the motion, so we must take it with a negative sign):
W_{net}=W-W_f=196.8 J-105.1 J=91.7 J
For the work-energy theorem, the work done on the block is equal to its increase of kinetic energy:
W_{net} = \Delta K
So, we have \Delta K=+91.7 J


5 0
3 years ago
What is science? Illustrate Ur views?​
jarptica [38.1K]

Answer:

Science is

Explanation:

he intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.

5 0
3 years ago
Read 2 more answers
The following diagram represents a cart with an initial velocity of 1.0 m/s sliding along a frictionless track from point A:
Phantasy [73]

Answer:

I believe it will it is B and D. Because they have the same shape and on both the cart wil be speeding up.

I HOPE THIS HELPS! HAVE A GREAT DAY! :)

5 0
3 years ago
Other questions:
  • I MARK BRAINLIEST, PLEASE ANSWER ASAP!!! PHYSICS 20 POINTS!!
    14·2 answers
  • At the top of the hill, the
    15·1 answer
  • A man 6 feet tall walks at a rate of 6 feet per second away from a light that is 15 feet above the ground.
    15·1 answer
  • WHAT FEATURE DO ALL VOLCANOES SHARE? PLEASE LIST AT LEAST 3!!!
    12·2 answers
  • What are the advantages of parallel circuits? Check all that apply
    11·2 answers
  • Which object is accelerating downward at the slowest rate? (1 point)
    8·1 answer
  • . Suppose that the displacement of an object is related to time according to the expression: x(t) = B t3 . Using dimensional ana
    12·1 answer
  • HELP PLEASE!! An illustration of a pendulum at 3 positions of a pendulum. The equilibrium position is labeled B. The other two p
    12·2 answers
  • A fairgrounds ride spins its occupants inside a flying saucer-shaped container. If the horizontal circular path the riders follo
    9·1 answer
  • Can anyone please tell me the properties of image formed in a spherical mirror?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!