All categories

3 years ago

What does it mean when work is positive?

Physics

2 answers:

Vedmedyk [2.9K]3 years ago

6 0

<h2>Answer:</h2>

d. An object did work on the environment.

<h2>Explanation:</h2>

Work is defined in many contexts. Some of these are;

i. <em>Work is the product of force and displacement</em>. In this case, work done is positive if the force applied on an object or body and the displacement caused by the force are in the same direction. If instead the force and displacement are in opposite direction, then the work done will be negative. If it is the case the force and the displacement are perpendicular to each other, the work done is zero.

ii. In the first law of thermodynamics, the internal energy of a system is the sum of the work done and the heat exchanged between the system and the environment. Therefore, <em>work done is the difference between the internal energy of a system and the heat exchanged between the system and the environment</em>.

In this case, work is said to be positive if work is done by the system (object) on the environment. It is negative if work is done by the environment on the system (object).

zhuklara [117]3 years ago

3 0

Answer:

C) The environment did work on an object

Explanation:

Edg

You might be interested in

4. An aluminium bar weighs 17 kg in air. How much force is required

kkurt [141]

Explanation:

1ml = 2.7g

Xml = 1.5g

Divide 1.5 by 2.7 to find X.

Obviously, since 1.5 is less than 2.7, you know the answer will be less than 1.

(it’s .5555555555)

4 0

3 years ago

The Moon orbits the Earth in an approximately circular path. The position of the moon as a function of time is given by: x(t) =

Aleks [24]

Answer: Average Velocity = - 643.42 i + 512.66 j m/s

Magnitude = 822.7 m/s

Direction = 141.45°

Explanation:

r = 3.84 x 10^8 m

w = 2.46 x 10^-6 rad/s

Formula for Average velocity = displacement / time

at t = 0

x(0) = r

y(0) = 0

at t = 8.45 days

= 8.45 x 24 x 3600 s =730080 sec

w t = 2.46 x 10^-6 x 730080 = 1.80 rad Or 102.90°

xf = r cos(w t) = - 0.2233r

yf = r sin(w t) = 0.9747r

Displacement = (xf - x0)i + (yf - y0)j = -1.2233r i + 0.9747r j

<v> = dispalcement / t = (-1.2233r i + 0.9747r j ) / (730080 s )

= - 643.42 i + 512.66 j m/s

Magnitude

= sqrt(643.42^2 + 512.66^2)

= 822.7 m/s

Direction

= 180 - tan^-1(512.66 / 643.42)

= 141.45°

8 0

3 years ago

Read 2 more answers

If a 2.0Ω resistor and a 4.0Ω resistor are connected with a 12 volt battery, what is the total resistance of the circuit?

makvit [3.9K]

answer:

6 ohms

Explanation:

if these two resistors are connected in series, the total resistance is the sum: 2+4 = 6 (ohms)

3 0

4 years ago

What are allotropes ?

Vikki [24]

Answer:

Explanation:

Allotropes are the elements that occur naturally in different forms in the nature.

For example Oxygen is in O2 state for breathing air and O3 in ozone layer.

Also C exits as diamond, graphite,coal and other numerous forms in nature.

5 0

3 years ago

A 60 w (120 v) night light is turned on for an average 12 h a day year round. part a what is the annual cost of electricity at a

Zinaida [17]

The annual cost of electricity is $28.908 .

work done is equal to energy consumed

therefore total energy is calculated as power times the duration of operation .

$W=P.t$

where W= work done

P=power

t= time of operation

therefore,

total work done (W)=0.06×12×365 kw

=262.8 kw

so total annual electricity bill = 262.8×0.11

=$28.908

Learn more about electricity bill consumption here:

brainly.com/question/21116164

#SPJ4

4 0

1 year ago