9514 1404 393
Answer:
17. 7.61×10³ N
18. 9.51 m/s²
19. maybe you want 29.375 N
Explanation:
17. Use the given formula for force. Fill in the masses and radius. The distance from the earth is in addition to the radius of the earth.
[tex]F=G\dfrac{m_1m_2}{r^2}\\\\F=(6.67\times10^{-11})\dfrac{5.97\times10^{24}\cdot 800}{((6.37+0.10)\times10^6)^2}=\dfrac{6.67\cdot5.97\cdot8.00}{6.47^2}\times10^3\\\\F=7.61\times10^3\qquad\text{newtons}[/tex]
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18. Make use of the relation ...
F = ma
a = F/m = (7.61×10³ N)/(800 kg)
a ≈ 9.51 m/s²
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19. The acceleration of the runner is ...
a = ∆v/∆t = (9 m/s - 4 m/s)/(8 s) = (5/8) m/s²
The force she is applying to the ground to accelerate herself is ...
F = ma = (47 kg)(5/8 m/s²) = 29.375 N
The amount of force applied to the tape depends on its mass and the effect the tape has on the runner's acceleration. There is insufficient information in the problem statement to permit an answer to the question.
