Answer:
c) 8.3 x 10^24 molecules
Explanation:
First of all, we convert the volume of the glass of water from mL to
:

The relationship between mass and volume is:

where
is the density of water
M is the total mass of the glass of water
is the volume of the water in the glass
Solving for M,

Now we know that the mass of a single molecule of water is

The total mass of the water in the glass can be written as

where
N is the number of molecules in the glass of water
Solving for N, we find:

Answer:
22 revolutions
Explanation:
2 rev/s = 2*(2π rad/rev) = 12.57 rad/s
The angular acceleration when it starting

The angular acceleration when it stopping:

The angular distance it covers when starting from rest:


The angular distance it covers when coming to complete stop:


So the total angular distance it covers within 22 s is 62.8 + 75.4 = 138.23 rad or 138.23 / (2π) = 22 revolutions
Velocity is defined by rate of change in the position
which we can also write as

while acceleration is defined as rate of change in velocity

so acceleration and velocity both are rate of change in position and rate of change in velocity with respect to time respectively
out of all above statement the correct answer must be
<u>Acceleration equals change in velocity divided by time. </u>
Answer:
B) The cosmic background radiation is expected to contain spectral lines of hydrogen and helium, and it does.
Explanation: