10.9 A spring balance has a spring constant of 3 lb/in, a basket with 6-lb potatoes
extends the spring 2.7 in. What is the weight of the basket?
10.10 A spring balance has a spring constant of 2.3 N/m. What is the deflection of the
balance when it is loaded with 0.73 N?
10.11 A force of 10 N is applied to a piston 150 cm in diameter in a closed cylinder. What
is the pressure in the cylinder?
10.12 What force is applied to a 9.2-in piston in a cylinder, if the pressure in the cylinder
is 23 psi?
10.13 What is the wavelength of 13 kHz sound waves?
10.14 What is the frequency of radar waves whose wavelength is 2.5 cm?
10.15 A person is 375 m from a bell and a second person is 125 m from the bell. What
is the difference in the sound levels of the bell rings heard by the two people?
10.16 What is the sound pressure level corresponding to 67 dB?
10.17 The light intensity 20 ft from a light bulb is 3.83 dB higher than at a second point.
What is the distance of the second point from the bulb?
10.18 What is the change in light intensity when the distance from the light source is
increased from 35 to 85 ft?
10.19 What is the angular displacement that can be sensed by an angular displacement
sensor, if the circular disc on a shaft has 115 slots and the photodiode array has 16
diodes? See Fig. 10.3.
10.20 The rotational speed of a steel cog wheel is being sensed with a magnetic sensor.
If the wheel has