(a) People often think of humid air as "heavy." Compare the densities of air with 0% relative humidity and 100% relative humidity when both are at 1 atm and 30 ℃. Assume that the dry air is an ideal gas composed of molecules with a molar mass of 29.0 g/mol and the moist air is the same gas mixed with water vapor. (b) As discussed in the chapter on the applications of Newton's laws, the air resistance felt by projectiles such as baseballs and golf balls is approximately F D = C p A v 2 / 2 , where p is the mass density of the air, A is the cross-sectional area of the projectile, and C is the projectile's drag coefficient. For a fixed air pressure, describe qualitatively how the range of a projectile changes with the relative humidity. (c) When a thunderstorm is coming, usually the humidity is high and the air pressure is low. Do those conditions give an advantage or disadvantage to home-run hitters?
(a) People often think of humid air as "heavy." Compare the densities of air with 0% relative humidity and 100% relative humidity when both are at 1 atm and 30 ℃. Assume that the dry air is an ideal gas composed of molecules with a molar mass of 29.0 g/mol and the moist air is the same gas mixed with water vapor. (b) As discussed in the chapter on the applications of Newton's laws, the air resistance felt by projectiles such as baseballs and golf balls is approximately F D = C p A v 2 / 2 , where p is the mass density of the air, A is the cross-sectional area of the projectile, and C is the projectile's drag coefficient. For a fixed air pressure, describe qualitatively how the range of a projectile changes with the relative humidity. (c) When a thunderstorm is coming, usually the humidity is high and the air pressure is low. Do those conditions give an advantage or disadvantage to home-run hitters?
(a) People often think of humid air as "heavy." Compare the densities of air with 0% relative humidity and 100% relative humidity when both are at 1 atm and 30 ℃. Assume that the dry air is an ideal gas composed of molecules with a molar mass of 29.0 g/mol and the moist air is the same gas mixed with water vapor. (b) As discussed in the chapter on the applications of Newton's laws, the air resistance felt by projectiles such as baseballs and golf balls is approximately
F
D
=
C
p
A
v
2
/
2
, where p is the mass density of the air, A is the cross-sectional area of the projectile, and C is the projectile's drag coefficient. For a fixed air pressure, describe qualitatively how the range of a projectile changes with the relative humidity. (c) When a thunderstorm is coming, usually the humidity is high and the air pressure is low. Do those conditions give an advantage or disadvantage to home-run hitters?
2
C01: Physical Quantities, Units and Measurementscobris alinu zotinUD TRO
Bendemeer Secondary School
Secondary Three Express Physics
Chpt 1: Physical Quantities, Unit and Measurements Assignment
Name: Chen ShiMan
loov neowled soria
25
( 03 ) Class: 3 Respect 6 Date: 2025.01.22
1
Which group consists only of scalar quantities?
ABCD
A
acceleration, moment and energy store
distance, temperature and time
length, velocity and current
mass, force and speed
B
D.
B
Which diagram represents the resultant vector of P and Q? lehtele
시
bas siqpeq olarist of beau eldeo qirie-of-qi
P
A
C
-B
qadmis
rle mengaib priwollot erT S
Quilons of qira ono mont aboog
eed indicator
yh from West
eril to Inioqbim srij
enisinoo MA
(6)
08 bas 8A aldao ni nolent or animaleb.gniweb slepe eld
260 km/h
D
1
D.
e
51
The figure gives the acceleration a versus time t for a particle moving along an x axis. The a-axis scale is set by as = 12.0 m/s². At t = -2.0
s, the particle's velocity is 11.0 m/s. What is its velocity at t = 6.0 s?
a (m/s²)
as
-2
0
2
t(s)
4
Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Knowing that the average normal stress must not
exceed 150 MPa in either rod, determine the smallest allowable values of the diameters d₁ and d2. Take P= 85 kN.
P
125 kN
B
125 kN
C
0.9 m
1.2 m
The smallest allowable value of the diameter d₁ is
The smallest allowable value of the diameter d₂ is
mm.
mm.
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.