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
34kurt
3 years ago
7

Use the law of conservation of energy to explain why the work output of a machine can never exceed the work input

Physics
2 answers:
Veronika [31]3 years ago
7 0

The law of conservation of energy states that energy is not created nor destroyed, rather it is only transferred or transmitted from one form to another. Now, the work exerted which is the input is only transformed to move the object which is now becomes the output work. Some are used to move the object, some are converted to other forms. That is why it is never greater than the input energy. Thank you for your question. Please don't hesitate to ask in Brainly your queries. 
abruzzese [7]3 years ago
4 0

Answer:

Explanation:

According to the law of energy conservation- energy of a closed system can neither be created nor be destroyed it can be only transformed. In a machine we get supply of input which get converted into different forms, we can not create any additional energy as input so it is possible that all the input energy converts into output( extreme case, when losses are zero) otherwise input energy coverts into many other form(heat, friction,etc) in the process of generating output. So output of a machine can never exceeds the input.

You might be interested in
A coil has 400 turns and self-inductance 7.50 mH. The current in the coil varies with time according to i = 1680 mA2 cos [πt/(0.
zhannawk [14.2K]

Answer:

(a) 1.58 V

(b) 0.0126 Wb

(c) 0.0493 V

Solution:

As per the question:

No. of turns in the coil, N = 400 turns

Self Inductance of the coil, L = 7.50 mH = 7.50\times 10^{- 3}\ H

Current in the coil, i = 1680cos[\frac{\pi t}{0.0250}] A

where

i_{max} = 1680\ mA = 1.680\ A

Now,

(a)  To calculate the maximum emf:

We know that maximum emf induced in the coil is given by:

e = \frac{Ldi}{dt}

e = L\frac{d}{dt}(1680)cos[\frac{\pi t}{0.0250}]

e = - 7.50\times 10^{- 3}\times \frac{\pi}{0.0250}\times \frac{d}{dt}(1680)sin[\frac{\pi t}{0.0250}]

For maximum emf, sin\theta should be maximum, i.e., 1

Now, the magnitude of the maximum emf is given by:

|e| = 7.50\times 10^{- 3}\times 1680\times 10^{- 3}\times \frac{\pi}{0.0250} = 1.58\ V

(b) To calculate the maximum average flux,we know that:

\phi_{m, avg} = L\times i_{max} = 7.50\times 10^{- 3}\times 1.680 = 0.0126\ Wb

(c) To calculate the magnitude of the induced emf at t = 0.0180 s:

e = e_{o}sin{\pi t}{0.0250}

e = 7.50\times 10^{- 3}\times sin{\pi \times 0.0180}{0.0250} = 2.96\times 10^{- 4} =0.0493\ V

7 0
3 years ago
A horizontal rectangular surface has dimensions 2.80 cm by 3.20 cm and is in a uniform magnetic field that is directed at an ang
koban [17]

Answer:

magnitude of the magnetic field 0.692 T

Explanation:

given data

rectangular dimensions = 2.80 cm by 3.20 cm

angle of 30.0°

produce a flux Ф = 3.10 × 10^{-4}  Wb

solution

we take here rectangular side a and b as a = 2.80 cm and b = 3.20 cm

and here angle between magnitude field and area will be ∅ = 90 - 30

∅ = 60°

and flux  is express as

flux Ф = \int \vec{B}.d\vec{A}   .................1

and Ф = BA cos∅    ............2

so B = \frac{\phi }{Acos\theta }    

and we know

A = ab

so

B = \frac{\phi }{abcos\theta }    ..............3

put here value

B =  \frac{3.10\times 10^{-4} }{2.80 \times 10^{-2}\times 3.20 \times 10^{-2}\times cos60}  

solve we get

B = 0.692 T

8 0
3 years ago
A swimming pool is 50 ft wide and 100 ft long and its bottom is an inclined plane, the shallow end having a depth of 4 ft and th
Nina [5.8K]

Explanation:

We define force as the product of mass and acceleration.

F = ma

It means that the object has zero net force when it is in rest state or it when it has no acceleration. However in the case of liquids. just like the above mentioned case, the water is at rest but it is still exerting a pressure on the walls of the swimming pool. That pressure exerted by the liquids in their rest state is known as hydro static force.

Given Data:

Width of the pool = w = 50 ft

length of the pool = l= 100 ft

Depth of the shallow end = h(s) = 4 ft

Depth of the deep end = h(d) = 10 ft.

weight density = ρg = 62.5 lb/ft

Solution:

a) Force on a shallow end:

F = \frac{pgwh}{2} (2x_{1}+h)

F = \frac{(62.5)(50)(4)}{2}(2(0)+4)

F = 25000 lb

b) Force on deep end:

F = \frac{pgwh}{2} (2x_{1}+h)

F = \frac{(62.5)(50)(10)}{2} (2(0)+10)

F = 187500 lb

c) Force on one of the sides:

As it is mentioned in the question that the bottom of the swimming pool is an inclined plane so sum of the forces on the rectangular part and triangular part will give us the force on one of the sides of the pool.

1) Force on the Rectangular part:

F = \frac{pg(l.h)}{2}(2(x_{1} )+ h)

x_{1} = 0\\h_{s} = 4ft

F = \frac{(62.5)(100)(2)}{2}(2(0)+4)

F =25000lb

2) Force on the triangular part:

F = \frac{pg(l.h)}{6} (3x_{1} +2h)

here

h = h(d) - h(s)

h = 10-4

h = 6ft

x_{1} = 4ft\\

F = \frac{62.5 (100)(6)}{6} (3(4)+2(6))

F = 150000 lb

now add both of these forces,

F = 25000lb + 150000lb

F = 175000lb

d) Force on the bottom:

F = \frac{pgw\sqrt{l^{2} + ((h_{d}) - h(s)) } (h_{d}+h_{s})   }{2}

F = \frac{62.5(50)\sqrt{100^{2}(10-4) } (10+4) }{2}

F = 2187937.5 lb

7 0
3 years ago
A tree moves at 30 km/s relative to the Sun. A squirrel jumps from a branch on
tresset_1 [31]

The reasoning is wrong if we look into Newton's Law of gravitation.

Newton's law of gravitation states  that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

The law is written as follows;

F = \frac{Gm_1m_2}{r^2}

r = \sqrt{\frac{Gm_1m_2}{F} }

The distance between the two particles, is a function of force and their masses not necessarily time of motion.

In the given problem only time of motion was considered which is wrong.

Thus, the reasoning is wrong if we look into Newton's Law of gravitation.

Learn more here: brainly.com/question/19680441

7 0
3 years ago
Helllppp mee!
Fed [463]

Given:

m = 0.14 kg

v = 18 m/s

To find:

Kinetic energy= ?

Explanation:

Kinetic energy of the object is possessed when the object is in motion. It is define as the work done required to accelerate a body from rest to motion. Unit of energy is Joule and it is same as unit of work done. Energy is nothing but the capacity to do work.

Solution:

Kinetic energy of the ball is given by,

Kinetic energy = \frac{1}{2}m v^{2}

m = 0.14 kg

v = 18 m/s

Kinetic energy = \frac{1}{2}(0.14) (18)^{2}

Kinetic energy = 226.8 Joule

5 0
3 years ago
Read 2 more answers
Other questions:
  • Substance that does not contain any free ions and will not be an electrically conductive medium is what?
    12·2 answers
  • If you walk 1.2 km north and then 1.6 km east, what are the magnitude and direction of your resultant displacement?
    13·1 answer
  • Explain why it is important to check your brake fluid regularly. explain what happens to the fluid when you step on the brake of
    12·1 answer
  • The human ear canal is about 2.3 cm long. If it is regarded as a tube open at one end and closed at the eardrum, what is the fun
    13·1 answer
  • How do the individual forces compare when the rider experiences a sensation being lighter than his normal weight ? What is the a
    8·1 answer
  • 6 An object can never have
    12·1 answer
  • What must be the reaction force when someone hits a tree with an axe?
    12·1 answer
  • Where does the cart have the most velocity(speed)?
    14·2 answers
  • Problem (2): Two point charged particles are 4.41cm apart. They are moved and placed in a new position. The force between them i
    7·1 answer
  • A boulder of mass 10 kg rolls over a cliff and reaches the beach below with a velocity of 15 m/s. Find:
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!