Work formula is Work=N∙M or Joule (J)
So you have the following given:
50 000 is the output work
.8 is the efficiency
if you input the given = 50000 = .8*J
To get the answer just divide 50000 by .8 to get the answer.
62,500 J is the amount of work to be done.

The correct choice is ❝ A ❞
❖ whєn wє tαlk αвσut α pєndulum, ít gσєѕ thrσugh ❝ tσ αnd frσ ❞ mσtíσn, αlѕσ knσwn αѕ hαrmσníc mσtíσn. αѕ вєíng ín thє cαѕє σf α pєndulum, thєrє'ѕ α cσntínuσuѕ chαngє ín kínєtíc αnd pσtєntíαl єnєrgч.
❖ whєn thє вσв íѕ αt mєαn pσѕítíσn, ít hαѕ ítѕ mαхímum vєlσcítч, αnd thє nєt fσrcє αnd αccєlєrαtíσn αctíng σn ít íѕ zєrσ, thєrєfσrє ít hαѕ mαхímum kínєtíc єnєrgч αt thαt pαrtículαr ínѕtαnt.
❖ whєrє αѕ, íf thє вσв íѕ αt σnє σf thє єхtrєmє pσѕítíσnѕ, ítѕ vєlσcítч вєcσmєѕ zєrσ, αnd thє αccєlєrαtíσn αnd fσrcє αctíng σn ít íѕ mαхímum, ѕímcє ít hαѕ nσ vєlσcítч, thєrєfσrє ít hαѕ nσ kínєtíc єnєrgч αt thαt ínѕtαnt, thє σnlч єnєrgч ít hαѕ αt thαt tímє íѕ pσtєntíαl єnєrgч.
❖ ѕíncє thє mσvєmєnt íѕ cσntínuσuѕ, cσntínuσuѕ chαngє ín єnєrgч σccurѕ, вut thє ѕum σf вσth thє єnєgíєѕ rєmαínѕ cσnѕtαnt αt єvєrч ínѕtαnt.

Answer:
joule
Explanation:
Let m = mass of the car and v1 = initial velocity and v2 = final velocity
Given.
Initial velocity = 100 km/h
final velocity = 50 km/h
What is work done in the car to slow it from 100km/h to 50km/h?


The work done in the car to slow it from v1 to v2.
w=Δk






joule.
Therefore, the work done is
joule
The density of an object is given by:
D = M/V
D = density, M = mass, V = volume
The volume of the cube V is given by:
V = s³
where s = side length
Make a substitution:
D = M/s³
Given values:
M = 20kg, s = 20×10⁻²m
Plug in and solve for D:
D = 20/(20×10⁻²)³
D = 2500kg/m³
Answer:
12 cm
Explanation:
We shall use Lens makers formula here which is as follows

Put μ = 1.5 , R₁ = 10 cm ,R₂ = - 15 cm ( according to sign convention )

= .5 x ( 15 + 10 ) / 15 x 10
= 
F = 12 cm