- #1

aqryus

- 6

- 1

- Homework Statement
- A deep space probe of mass 4.55 x10^4kg is travelling at an initial speed of 1.22 x10^4

m/s. The engines of the probe exert a force of magnitude 3.85 x10^5

N over 2.45 x10^8 m. Determine the probes final speed

- Relevant Equations
- W=Ek2-Ek1

W=fd

W=(1/2)mv2^2-(1/2)mv1^2

First I found work:

W=(3.85x10^5)(2.45x10^8)

W= 9.43x10^13

Then used that for difference of kinetic energy:

9.43x10^13 = (1/2) (4.55x10^4)v2^2 - (1/2)(4.55x10^4)(1.22x10^4)^2

9.43x10^13 = (22750)v2^2 - 3.386x10^12

9.43x10^13 + 3.386x10^12 = (22750)v2^2

9.77x10^13 = 22750v2^2

9.77x10^13/22750 = v^2

squareroot 4.3x10^6 = v

6.55x10^4 = v

But the answer is 1.38x10^4 m/s? I'm not sure where I went wrong. Any help is appreciated

W=(3.85x10^5)(2.45x10^8)

W= 9.43x10^13

Then used that for difference of kinetic energy:

9.43x10^13 = (1/2) (4.55x10^4)v2^2 - (1/2)(4.55x10^4)(1.22x10^4)^2

9.43x10^13 = (22750)v2^2 - 3.386x10^12

9.43x10^13 + 3.386x10^12 = (22750)v2^2

9.77x10^13 = 22750v2^2

9.77x10^13/22750 = v^2

squareroot 4.3x10^6 = v

6.55x10^4 = v

But the answer is 1.38x10^4 m/s? I'm not sure where I went wrong. Any help is appreciated

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