Answer:

Explanation:
given,
moles of air compressed, n = 1.70 mol
initial temperature, T₁ = 390 K
Power supply by the compressor, P = 7.5 kW
Heat removed = 1.3 kW
Angular frequency of the compressor, f = 110 rpm = 110/60 = 1.833 rps.
Time of compression = time of the hay revolution
=
=
=
=0.273 s
Using first law of thermodynamics
U = Q - W
now,

Power supplied
= 7.5 kW
heat removed
= 1.3 kW
now,


we know,

C_v for air = 5 cal/° mol
= 5 x 4.186 J/mol°C = 20.93 J/mol°C
now,



the temperature change per compression stroke is equal to 47.57°C.
Answer:
<h3>0.69</h3>
Explanation:
Using the Newtons law of motion;

Fm is the moving force = 400N
Ff is the frictional force = μR
μ is the coefficient of kinetic friction
R is the reaction = mg
m is the mass
a is the acceleration
The equation becomes;

Hence the coefficient of kinetic friction between the box and floor is 0.69
Answer:
For C is B and for D is A
Explanation:
B because that's where the b car will do all the force to go up, and A because there the car doesn't have to do any force other than the natural, and it already brings that on it's own.
Answer:
E. Coefficient of linear expansion
We use the law of Cosines, resultant force

Here,
and
are forces acting at angle
with each other.
Given
,
and
.
Substituting these given values in above formula we get
.
Thus, the resultant force is 156 N.