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2 years ago

What is the speed of an 800 kg automobile if it has a kinetic energy of 9.00 x 10^J?

Physics

1 answer:

MA_775_DIABLO [31]2 years ago

7 0

Ek = 1/2 mv^2

9 × 10^4 = 1/2 × 800 × v^2

9 × 10^4/400 = 400 v^2 / 400

9 × 10^4/400 = v^2

√225 = v

15 ms⁻¹ = v

That's the only way I know how to work it out

I think in this case velocity and speed would be considered the same because me

s = d/t and v=d/t

one is distance travelled and the other is displacement of a body

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$I_3 = I_2 cos^2(\theta_2 - \theta_1 )$

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$I_p = \frac{2L_3}{(cos^2 \theta [cos^2 (\theta_2 - \theta_1)])}$

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$I_p = \frac{2 * 60 }{(cos^2(21) [cos^2 (40)])}$

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When the second is removed the third polarizer becomes the second and final polarizer so the intensity of light would be mathematically evaluated as

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When the third polarizer is removed the second polarizer becomes the

the final polarizer and the intensity of light emerging from the stack would be

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