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
Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by

where
is the coefficient of friction and
is the normal force.
When the student pulls on the block with force
at an angle
, the normal force on the block becomes

and hence the frictional force becomes
.
Now, as we increase
,
increases which as a result decreases the normal force
, which also means the frictional force decreases; Hence choice B stands true.
<em>P.S: Choice D is tempting but incorrect since the weight </em>
<em> is independent of the external forces on the block. </em>
Answer:

Explanation:
From the question we are told that:
Mass of block 
Temperature of block 
Volume of water 
Temperature of water 
Density of water 
Specific heat of water 
Specific heat of copper 
Generally the equation for equilibrium stage is mathematically given by









Answer is OB
Answer is OB
Answer is OB
Answer:
true
Explanation:
i think it's true because I took a quiz on this