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3 years ago

A 1280 kg car is moving 4.92 m/s. a 509 N force then pushes it forward for 28.7 m. what is its final KE?(unit=J)PLEASE HELP

Physics

2 answers:

laila [671]3 years ago

8 0

Answer:

The answer to your question is: total energy = 30100.4 J

Explanation:

Kinetic energy (KE) is the energy due to the movement of and object, its units are joules (J)

Data

mass = 1280 kg

speed = 4.92 m/s

Force = 509 N

distance = 28.7 m

Formula

$KE = \frac{1}{2} mv^{2}$

Work = Fd

Process

- Calculate Kinetic energy

- Calculate work

- Add both results

KE = $\frac{1}{2} (1280)(4.92)^{2}$

KE = 15492.1 J

Work = (509)(28.7)

Work = 14608.3 J

Total = 15492.1 + 14608.3

Total energy = 30100.4 J

Elden [556K]3 years ago

3 0

Answer:

30,100 J

Explanation:

Work = change in energy

W = KE₂ − KE₁

Fd = KE − ½ mv²

(509 N) (28.7 m) = KE − ½ (1280 kg) (4.92 m/s)²

KE = 30,100 J

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