Respuesta :
Answer:
64.10937 N
Explanation:
s = Displacement
v = Velocity
F = Force
Converting hp to W
[tex]2.75\times 746=2051.5\ W[/tex]
Work
[tex]W=F\times s[/tex]
Power
[tex]P=\frac{W}{t}\\\Rightarrow P=\frac{F\times s}{t}[/tex]
Now
[tex]\frac{s}{t}=v[/tex]
So,
[tex]P=F\times v\\\Rightarrow F=\frac{P}{v}\\\Rightarrow F=\frac{2051.5}{32}\\\Rightarrow F=64.10937\ N[/tex]
The friction force acting on the van is 64.10937 N
Answer:
The friction force on the van is 64.11 N
Solution:
As per the question:
Power developed by the van engine, P = 2.75 hp
Speed of the van, v = 32 m/s
Since, 1 hp = 746 W
Thus
P = [tex]2.75\times 746 = 2051.5 W[/tex]
Now, we know that:
Work done is given as the product of force and displacement:
W = Fd (1)
where
W = Work done
F = Force
d = displacement
Also,
[tex]P = \frac{dW}{dt}[/tex] (2)
where
t = time
Therefore, from eqn (1) and (2):
[tex]P = \frac{d}{t}(Fd)[/tex]
Since, the van is travelling with constant speed, Force is constant:
P = Fv
[tex]F = \frac{P}{v} = \frac{2051.5}{32} = 64.11\ N[/tex]
- Since, this force is applied by the engine in order to maintain the speed and hence is equal to the friction force that acts on the van.