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Physics LibreTexts

4.8: Unit 4 Practice and Assessment

  • Page ID
    17736
  • Outcome 1

    1) Which has greater density between a kilogram of feathers and a kilogram of pennies? Which has greater volume? Which has greater mass?

    Outcome 2

    2) What is the weight in Newtons of a 3 kg textbook?

    3) Convert your own weight from pounds to Newtons. Then calculate your mass in kilograms. Show all work.

    4) The acceleration due to gravity (g) on the moon is 1/6 that on the surface of Earth. Based on your answers to the previous question, what would your weight be on the moon? What would your mass be on the moon?

    Outcome 3

    4) A 7 N force pushes on an object to the right and a 7 N force pushes on the object to the left. What is the net force? Can the object be in static equilibrium?

    5) A 5 N force pushes on an object to the right and a 7 N force pushes on the object to the left. What is the net force? Can the object be in static equilibrium?

    6) You push on a large box with 120 N of force, but it doesn’t move. How large is the friction force? Draw a free body diagram of the situation.

    7) Helping a 48 lb toddler learn to float in a swimming pool you notice that it feels as though they only weigh 5 lbs. How large is the buoyant force on the toddler? Draw a free body diagram of the situation.

    Outcome 4

    8) What weight of water must the toddler in the previous question be displacing?

    9) An object has a volume of 0.5 m3. What is the maximum volume of water it can displace? What weight of water can it displace?

    10) The object in the previous problem has a weight of 150 N. Will it float?

    11) Is the object in the previous problem more or less dense than water?

    Outcome 5

    11) Calculate the density of the object referred to in the previous problem.

    12) An object has a weight of 5.5 N and an apparent weight of 3.5 N when fully submerged. Will the object float?

    13) Calculate the density of the object in the previous problem.