A) the pump removes air from the enclosure. foam absorbs vibrations from the clock
b) result is that as the air is taken out by pump, the sound of alarm reduces and eventually becomes zero. so, you cant hear the alarm ringing.
c) conclusion is that sound cant travel in vaccum and it requires a medium to travel.
Answer:
Explanation:
STEP 1
<u>Given</u>
Radius of cylinder = r = 25cm, 2.5m
mass = 27kg
cylinder is mounted so as to rotate freely about a horizontal axis that is parallel to and 60cm to the central logitudinal axis of the cylinder
height = 0.6m
<u>part 1</u>
The cylinder is mounted so as to rotate freely about a horizontal axis tha is paralle to 60cm from the central longitudinal axis of then cylinder. The rotational inertia of the cylinder about the axis of rotation is given by
<em>I = Icm + mh²</em>
<em>∴ I = 1/2mr² + mh² = 1/2x27x (0.5)² + 20 x (0.6)²</em>
<em>I=13.09kg.m²</em>
where
<em>I</em>cm is the rotational inertia of the cylinder about its central axis
m is the mass of the cylinder
h is the distance between the axis of the rotation and the central axis of the cylinder
r is the radius of the cylinder
<em> </em><em> I=13.09kg.m²</em>
<em>part2</em>
<em>from the conservation of the total mechanical energy of the meter stick, the change in gravitational potential energyof the meter stick plus the change in kinetic energy must be zero</em>
<em>Δk + Δu = 0</em>
<em>1/2 </em>I(w²-w²) = Ui-Uf
1/2 x 13.09w² = mgh
∴w=√20 x 9.8 x 0.6/(1/2 x 13.09) =117.6/6.5
w=18.09rad/s
Answer:
B
Explanation:
did this yesterday with my friend
Here we can use coulomb's law to find the force between two charges
As per coulombs law
]tex]F = \frac{kq_1q_2}{r^2}[/tex]
here we have
now by using the above equation we have
so here the force between two charges is of above magnitude and this will be repulsive force between them as both charges are of same sign.
