KINS 382 LAB 12

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KINS 382 - LAB 12

• Newtons Laws Problem Set 2

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Question 1

• Shannon Miller (125 pounds) does a 2-handed
  handstand. If she is in a perfectly symmetrical
  position, what is the upward normal force on one
  of her hands.

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Answer 1

• Wt 125 lbs.
• Force on 1 arm ?
• 125lbs X 4.45N / 1lb 556.25 N
• 1/2 (556.25N) 278.12 N or
• 1/2 (125lbs.) 62.5 lbs.

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Question 2

• What would the air resistance (drag) have to be
  when a 200 pound skydiver reaches terminal
  velocity (in Newtons)?

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Answer 2

• F (down, caused by weight) 200lbs.
• F (up caused by drag) ?
• Force is given in pounds convert 200lbs. to N
• 200lb X 4.45 N / 1lbs 890 N

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Question 3

• If Mark weighs 165 pounds on Earth and 100 pounds
  on the moon, what is his acceleration due to
  gravity on the moon?

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Answer 3

• Wt (Earth) 165 lbs.
• Wt (Moon) 100 lbs.
• F (m)(a) a F/m
• Find mass on Earth,
  165 lbs. X 1kg/2.2lb 75kg
• Find force on the Moon,
  100 lb X 4.45N/1lb 445 kg m/s²

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Answer 3, Cont

• What do we know, Mass 75kg and Force
  445 N (On the Moon), What is acceleration (On
  the Moon).
• a F/m
• a 445 (kg)m/s² / 75kg 5.93 m/s²

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Question 4

• My suitcase weighs 68 pounds.
• If I pull upwards with 200 N of force, will it
  move off the ground?
• How about if I pull with 400 N.

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Answer 4

• Wt 68lbs, F1 200N, F2 400N, Force required
  to move the suitcase ?
• 68 lbs X 4.45N / 1lb 302.6 N
• F1 will not move the suitcase.
• F2 will move the suitcase.

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Question 5

• If Chris weighs 260 pounds and Steve Young weighs
  210 pounds, what is the attractive force between
  them if they are 25 yards apart?

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Answer 5

• Chris M1 260 pounds
• Steve Young M2 210 pounds
• distance r 25 yards.
• Formula F (G)m1m2 / d2
• Convert all of the variables.
• 260lbs X 1kg/2.2lb 118.18kg
• 210lbs X 1kg/2.2lb 95.45kg
• 25 yards X 1m/1.09yd 22.94m

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Answer 5, Cont

• Formula F (G)m1m2 / d2
• G 6.67 X 10 -11 Nm²/kg²
• F 6.67 X 10 -11 Nm²/kg²(118.18kg) (95.45kg) /
  (22.94m)²
• F 6.67 X 10 -11 Nm²/kg² (11280.28kg²) /
  564.24m²
• F 75239.47 X 10 -11 N / 562.24
• F 142.99 X 10 -11 N or 1.42 X 10 -9 N

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Question 6

• How much matter is in a 12 pound shotput?
• Can that change depending on location and the
  force of gravity?

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Answer 6

• Wt 12 lbs
• Matter ?
• 12 lbs X 1kg/2.2lb 5.45kg
• Matter never changes!
• Force and Weight do change contingent upon
  gravity.

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Question 7

• A 20 pound weight on a spring that resists
  stretching of up to 50N.
• Does this weight compress the spring?
• What about if the weight is 10 pounds?

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Answer 7

• Wt1 20 lbs, Wt2 10 lbs, F 50N
• 20lb X 4.45N/1lb 89N, Spring will compress
• 10lb X 4.45N/1lb 44.5N, Spring will not compress

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Question 8

• The Washington Monument weighs 4 tons. Kaden
  weighs 200 pounds. Kaden is standing 2 miles
  away in the White House, what is the force of
  attraction between them?
• 1 ton 2000 pounds
• Convert your answer to scientific notation.

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Answer 8

• Monument 4 tons (Not really but this is the
  number well use for the problem).
• Kaden 200lbs
• distance 2 miles
• F ?
• Formula F (G)m1m2 / d2

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Answer 8, Cont

• Convert all Variables.
• m1 4tons 8000lbs X 1kg/2.2lb 3636.36kg
• m2 200lbs X 1kg/2.2lb 90.91kg
• d 2miles X 1609.35m/1mile 3218.7m
• Given m1 3636.36kg, m2 90.91kg, d 3218.7m

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Answer 8, Cont

• Formula F (G)m1m2 / d2
• F 6.67 X 10 -11 Nm²/kg² (90.91kg) (3636.36kg) /
  (3218.7m)²
• F 6.67 X 10 -11 Nm²/kg² (330581.49kg²) /
  10360029.69 m²
• F 2,204,978.54 X 10 -11 N / 10,360,029.69
• F .21 X 10 -11 N or 2.10 X 10 -12 N

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Conclusion