The pump in a vacuum cleaner is merely

Ivy Bucsa

PHY=102

August 17, 2014

Lillian Flakes

Chapter 5,6 and 7 Assignments

Chapter 5

Plug and Chug

49. The depth of water behind the Hoover Dam is 220 m.

Show that the water pressure at the base of this dam is

2160 kPa

Think and Solve

51. Suppose you balance a 2-kg ball on the tip of your finger,

which has an area of 1 cm2. Show that the pressure on

your finger is 20 N/cm2, or is 200 kPa.

Exercises

74. Stand on a bathroom scale and read your weight. When

you lift one foot up so you’re standing on one foot, does

the reading change? Does a scale read force or pressure?

91. The “pump” in a vacuum cleaner is merely a high-speed

fan. Would a vacuum cleaner pick up dust from a rug on

the Moon? Explain

94. Your friend says that the buoyant force of the atmosphere

on an elephant is significantly greater than the buoyant

force of the atmosphere on a small helium-filled balloon.

What do you say?

101. The force of the atmosphere at sea level against the outside

of a 10@m2 store window is about 1 million N. Why

doesn’t this shatter the window? Why might the window

shatter in a strong wind blowing past?

Discussion Questions

108. The photo shows physics

teacher Marshall Ellenstein

walking barefoot

on broken glass bottles

in his class. What physics

concept is Marshall

demonstrating, and why

is he careful that the broken

pieces are small and

numerous? (The Band-

Aids on his feet are for

Humor

114. If liquid pressure were the same at all depths, would there

be a buoyant force on an object submerged in the liquid?

Discuss your explanation of this with your friends

Chapter 6 Review

Think and Rank

47. The precise volume of water in a beaker depends on the

temperature of the water. Rank from greatest to least the

volume of water at these temperatures: (a) 0°C, (b) 4°C,

and (c) 10°C55. After a car is driven along a road for some distance, why

does the air pressure in the tires increase?

E55. After a car is driven along a road for some distance, why

does the air pressure in the tires increase?xercises

Discussion Questions

77. On cold winter nights in days past, it was common to bring

a hot object to bed with you. Which would keep you warmer

through the cold night: a 10-kg iron brick or a 10-kg jug of

hot water at the same high temperature? Explain.

78. Why does the presence of large bodies of water tend to

moderate the climate of nearby land—making it warmer

in cold weather and cooler in hot weather?

Chapter 7 Review

Think and Solve

Exercises

60. What is the purpose of the copper or aluminum layer on

the bottom of a stainless-steel pot?

62. Many tongues have been injured by licking a piece of

metal on a very cold day. Why would no harm result if a

piece of wood were licked on the same day?

81. Why does wrapping a bottled beverage in a wet cloth at

a picnic often produce a cooler bottle than placing the

bottle in a bucket of cold water?

85. When boiling spaghetti, is your cooking time reduced if

the water is vigorously boiling instead of gently boiling

Discussiom Questions

97. When you are near an incandescent lamp, turn it on

and off quickly. You feel its heat, but you find when you

touch the bulb that it is not hot. Explain why you felt

heat from the lamp.

109. Why is a tub of water placed in a farmer’s canning cellar

in cold winters to help prevent canned food from

freezing?

110. Why does spraying fruit trees with water before a frost

help protect the fruit from freezing?

Paper must be finished in ApA format Times Roman 12 I do not know how to send illustrations from my textbook. Sorry for the inconvience!!