Answer:
Work done against gravity will be
W = Mgℓ
Explanation:
Work done to raise the mass from ground to given height is against gravity
So here work done is given by the formula

here we know that

it is the force due to gravity which is also known as weight
so here distance moved by the object is given as
d = ℓ
now work done is given as
W = Mg ℓ
Answer:
One of Eight Planets : Earth
Spiral galaxy, One of the estimated billions of galaxies: Milky Way
Galaxy: Milky Way
Explanation:
According to the definition, appositive or apposition is a grammatical construction which represents similar noun phrases and nouns where one serves or defines the other one.
Here, the ultimate examples of apposition are mentioned in the given statement as Earth: One of Eight Planets, Milky Way: Spiral Galaxy and one of the estimated billions of galaxies: Milky Way.
With such kinds of words, it's easier to understand the noun or renames with a short definition written as a phrase.
Answer:
wave length is 1.2m
Explanation:
since formula of wave length is v/f
v(speed of sound in air at stp is 300ms^-1)
f(frequency 250hertz)
then wave length is 300÷250 which give 1.2m
Answer:
The ball is dropped at a height of 9.71 m above the top of the window.
Explanation:
<u>Given:</u>
- Height of the window=1.5 m
- Time taken by ball to cover the window height=0.15
Now using equation of motion in one dimension we have

Let u be the velocity of the ball when it reaches the top of the window
then

Now u is the final velocity of the ball with respect to the top of the building
so let t be the time taken for it to reach the top of the window with this velocity

Let h be the height above the top of the window

Answer:
The answer is A Ruler and Balance
Explanation: