Answer:
Approximately
.
Explanation:
This question suggests that the rotation of this object slows down "uniformly". Therefore, the angular acceleration of this object should be constant and smaller than zero.
This question does not provide any information about the time required for the rotation of this object to come to a stop. In linear motions with a constant acceleration, there's an SUVAT equation that does not involve time:
,
where
is the final velocity of the moving object,
is the initial velocity of the moving object,
is the (linear) acceleration of the moving object, and
is the (linear) displacement of the object while its velocity changed from
to
.
The angular analogue of that equation will be:
, where
and
are the initial and final angular velocity of the rotating object,
is the angular acceleration of the moving object, and
is the angular displacement of the object while its angular velocity changed from
to
.
For this object:
, whereas
.
The question is asking for an angular acceleration with the unit
. However, the angular displacement from the question is described with the number of revolutions. Convert that to radians:
.
Rearrange the equation
and solve for
:
.
Answer:
7500000 metres
Explanation:
1 kilometre = 1000 metres
so 7500 kilometres would equal to 7500000 metres
Answer:

Explanation:
Given that:
- mass of 1 skier,

- inclination of hill,

- length of inclined slope,

- time taken to reach the top of hill,

- coefficient of friction,

<em>Now, force normal to the inclined plane:</em>



<em>Frictional force:</em>



<em>The component of weight along the inclined plane:</em>



<em>Now the total force required along the inclination to move at the top of hill:</em>



<em>Hence the work done:</em>



<em>Now power:</em>



<u>So, power required for 30 such bodies:</u>




Answer:
P = 11666.6 W
Explanation:
Given that,
Work done by the motor, W = 3500 kJ
Time, t = 5 min = 300 s
We need to find the power developed by the motor. Power developed is given by :

So, the required power is 11666.6 W.
Answer:
0.37 m
Explanation:
Given :
Window height,
= 1.27 m
The flowerpot falls 0.84 m off the window height, i.e.
= (1.27 x 0.84 ) m in a time span of
seconds.
Assuming that the speed of the pot just above the window is v then,


![$v=\left(\frac{30}{8}\right) \left[ (1.27 \times 0.84) - \left( \frac{1}{2} \times 9.81 \times \left( \frac{8}{30 \right)^2 \right) \right]}$](https://tex.z-dn.net/?f=%24v%3D%5Cleft%28%5Cfrac%7B30%7D%7B8%7D%5Cright%29%20%5Cleft%5B%20%281.27%20%5Ctimes%200.84%29%20-%20%5Cleft%28%20%5Cfrac%7B1%7D%7B2%7D%20%5Ctimes%209.81%20%5Ctimes%20%5Cleft%28%20%5Cfrac%7B8%7D%7B30%20%5Cright%29%5E2%20%5Cright%29%20%5Cright%5D%7D%24)
m/s
Initially the pot was dropped from rest. So, u = 0.
If it has fallen from a height of h above the window then,


h = 0.37 m