According to the work-energy theorem, if work is done on an object, its potential and/or kinetic energy changes. Consider a car
1 answer:
Answer:
The force of the car engine.
Explanation:
The work- energy theorem states that the work done on an object is equal to the change in its kinetic energy. Its expression is given by :
Also, W = F.d
Where
F is the force applied by the engine of car
d is the displacement
m is the mass of an object
u is the initial speed
v is the final speed
So, the force of the car engine increased the car’s kinetic energy. Hence, this is the required solution.
You might be interested in
Answer:
1.034m/s
Explanation:
We define the two moments to develop the problem. The first before the collision will be determined by the center of velocity mass, while the second by the momentum preservation. Our values are given by,
<em>Part A)</em> We apply the center of mass for velocity in this case, the equation is given by,
Substituting,
Part B)
For the Part B we need to apply conserving momentum equation, this formula is given by,
Where here is the velocity after the collision.
Answer:
-40 kJ
80 kJ
Explanation:
Work is equal to the area under the pressure vs volume graph.
W = ∫ᵥ₁ᵛ² P dV
2.27) Pressure and volume are linearly related. When we graph P vs V, the area under the line is a trapezoid. So the work is:
W = ½ (P₁ + P₂) (V₂ − V₁)
W = ½ (100 kPa + 300 kPa) (0.1 m³ − 0.3 m³)
W = -40 kJ
2.29) Pressure and volume are inversely proportional:
pV = k
The initial pressure and volume are 500 kPa and 0.1 m³. So the constant is:
(500) (0.1) = k
k = 50
The final pressure is 100 kPa. So the final volume is:
(100) V = 50
V = 0.5
The work is therefore:
W = ∫ᵥ₁ᵛ² P dV
W = ∫₀₁⁰⁵ (50/V) dV
W = 50 ln(V) |₀₁⁰⁵
W = 50 (ln 0.5 − ln 0.1)
W ≈ 80 kJ
The relationship between resistance R and resistivity 
is
where L is the length of the wire and A its cross section.
The radius of the wire is half the diameter:
and the cross section is
From the first equation, we can then find the length of the wire when
(copper resistivity: 
)
where L is the length of the wire and A its cross section.
The radius of the wire is half the diameter:
and the cross section is
From the first equation, we can then find the length of the wire when