Answer:
T = 15 kN
F = 23.33 kN
Explanation:
Given the data in the question,
We apply the impulse momentum principle on the total system,
mv₁ + ∑
= mv₂
we substitute
[50 + 3(30)]×10³ × 0 + FΔt = [50 + 3(30)]×10³ × ( 45 × 1000 / 3600 )
F( 75 - 0 ) = 1.75 × 10⁶
The resultant frictional tractive force F is will then be;
F = 1.75 × 10⁶ / 75
F = 23333.33 N
F = 23.33 kN
Applying the impulse momentum principle on the three cars;
mv₁ + ∑
= mv₂
[3(30)]×10³ × 0 + FΔt = [3(30)]×10³ × ( 45 × 1000 / 3600 )
F(75-0) = 1.125 × 10⁶
The force T developed is then;
T = 1.125 × 10⁶ / 75
T = 15000 N
T = 15 kN
Answer:
230.4W
Explanation:
Heat transfer by conduction consists of the transport of energy in the form of heat through solids, in this case a jacket.
the equation is as follows

Where
Q=heat
k=conductivity=0.04
A=Area=1.8m^2
T2=33C
T1=1C
L=thickness=1cm=0.01m
Q=230.4W
the skier loses heat at the rate of 230.4W
Explanation:
Note: Refer the diagram below
Obtaining data from property tables
State 1:

State 2:

State 3:

State 4:
Throttling process 
(a)
Magnitude of compressor power input


(b)
Refrigerator capacity



(c)
Cop:


Answer:
Mechanical average of a wheel = 3
Explanation:
Given:
Radius of wheel = 1.5 ft = 1.5 x 12 = 18 inches
Radius of axle = 6 inches
Find:
Mechanical average of a wheel
Computation:
Mechanical average of a wheel = Radius of wheel / Radius of axle
Mechanical average of a wheel = 18 / 6
Mechanical average of a wheel = 3