The correct answer is: Option (A) 75 J
Explanation:
First, be careful with the units here. As you can see it is mentioned that there is a 50N box. It means that the weight (<em>mg</em>) of the box is given as the unit is <em>Newton</em>, not its mass (which is in kg).
As,
Potential-energy = mass * acceleration-due-to-gravity * height
PE = m*g*h --- (A)
In equation (A), mg is actually the weight of the box, which is given.
mg = 50N
h = height = 1.5m
Plug the values in equation (A):
PE = 50 * 1.5 = <em>75 J (Option A)</em>
I would say that this is the first law of thermodynamics.
Answer: A red supergiant
Explanation:
Red supergiants are the stars that have a supergiant luminosity which has a class of either K or M spectral type. In terms of volume, they are regarded as the largest stars on Earth even though they are not the most luminous.
Red supergiants are formed when a star collapses after the hydrogen fuel that the star has in its core runs out and
then fusion begins when the outer shells of hydrogen gets hot.
Answer:
The Autocratic system of governance
Explanation:
<em>Thi</em><em>s</em><em> is</em><em> </em><em>b</em><em>ecause</em><em>,</em><em>in </em><em>Autocratic</em><em> </em><em>sy</em><em>stem</em><em> </em><em>of</em><em> </em><em>gover</em><em>nance</em><em> </em><em>decis</em><em>ion</em><em> </em><em>maki</em><em>ng</em><em> </em><em>is</em><em> </em><em>don</em><em>e</em><em> </em><em>by</em><em> </em><em>onl</em><em>y</em><em> </em><em>indi</em><em>vidual</em><em>.</em><em> </em><em>And</em><em> </em><em>his</em><em>/</em><em>her</em><em> </em><em>dec</em><em>ision</em><em> </em><em>is</em><em> </em><em>fina</em><em>l</em><em>.</em>
<h2>Answer:</h2>
<u>Acceleration is </u><u>-10.57 rad/s² </u>
<u>Time is </u><u>6 seconds</u>
<h2>Explanation:</h2><h3>a) </h3>
u=900rpm= 94.248 rad/s
v =300rpm= 31.416 rad/s
s=60 revolutions= 377 rad
v²= u²+ 2as
31.416² = 94.248²+ 2 * a * 377
a = v²-u² / 2s
a= -10.57 rad/s²
<h3>b) </h3>
Using 1st equation of motion
v-u/a = t
Putting the values
t = (31.4 - 94.2)/-10.57
t = 6 seconds