# 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 **m ^{3}**. 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.