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1)
Car A has a mass of 1,000 kg and is traveling 60 km/hr. Car B has a mass of 2,000 kg and is traveling 30 km/hr. Compare the kinetic energy of car A with that of car B?
A) equal
B) half as much
C) twice as much
D) four times as much

Respuesta :

Stefanisaska

Answer: C

Explanation:

Calculate EkA -kinetic energy of car A

m=1000kg

Va=16.66 m/s

EkA=m*Va²/2

Eka=(1000kg*277.556m²/s²)/2

Eka=138 777.8 J

Calculate kinetic energy of CarB:

m=2000 kg

Vb=8.33 m/s

Ekb=(m*Vb²)/2

Ekb=(2000kg*69.39m²/s²)/2

Ekb=69 388.9 J

compare Eka with EkB

Eka/Ekb=138 777.8 J/69 388.9

Eka/Ekb=2

The kinetic energy of car A is  twice as much as car B. Option C is correct.  

Kinetic energy of car A:    

[tex]\bold {KEa = \dfrac 12 mv^2}[/tex]

Since, m =1000kg  

         Va =16.66 m/s  

Thus,

KEa = (1000 kg x 277.556m²/s²)/2  

KEa = 138 777.8 J

Kinetic energy of Car B:

Since ,

m = 2000 kg  

Vb = 8.33 m/s  

Thus,  

KEb =(2000 kg  x 69.39 m²/s²)/ 2  

KEb = 69 388.9 J

Now compare KEa with KEb  

KEa /KEb   = 138 777.8 J/ 69 388.9  

KEa /KEb   = 2

Therefore, the kinetic energy of car A is  twice as much as car B.

To know more about  kinetic energy,

https://brainly.com/question/999862

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