ME209
Homework #2
1- Write a program to input the coefficients of a quadratic equation and solve for the roots. Apply
your program to the equation
2
2
1,2
x 2x 3 0
4
2
b b ac
x
a
output your labeled input and labeled results.
2- Temperatures may be converted from Celsius to Fahrenheit using the formula
F=1.8C 32
Write a program to input the temperature in Celsius and convert it to Fahrenheit. Try your
program with C = -40°, C = 20°, and C = 100°.
(By the way, Excel have a conversion function called “convert”, I urge you to search the help file
to learn more about it).
3- Polar coordinates are related to Cartesian Coordinates by the following equations. Write a
program to input x = 2.5 and y = 7.1 to computer the r and θ. Then input r = 5.5 and θ = 49° to
compute x and y.
2 2 1
cos( ) sin( ) tan ( )
y
x r y r r x y
x
ME209
CSUN-Mechanical Engineering Department
Homework # 1
A parachutist jumps from a stationary platform. Until the rip cord is pulled, the jumper’s velocity can be
computed with the following equation:
( / ) ( / )
( ) (1 )d d
c m t c m t
o
d
gm
v t v e e
c
where v(t) is the downward velocity [m/s], v0 is the initial downward velocity, t is time [s], g is the
gravitational acceleration constant [≈9.81 m/s2], m is the jumper’s mass [kg], and cd is the drag coefficient
[kg/s], which parameterizes air resistance.
Develop an Excel workbook where the user can enter the mass, the drag coefficient, initial velocity, and
end time. The user should be able to see the calculated velocity of the time period [0,end_time] in table
and chart formats. Your submitted file should include:
1- Named Cells and Range
2- A properly created and labeled graph of velocity vs. time (i.e. good graph as we discussed in
class).
3- Table shows the calculated velocity at each time step.
4- Discuss the behavior of the jumper’s velocity as the velocity increase, i.e. as an engineer what
is the information you can extract from the equation above?
...
ME209 Homework #2 1- Write a program to input .docx
1. ME209
Homework #2
1- Write a program to input the coefficients of a quadratic
equation and solve for the roots. Apply
your program to the equation
2
2
1,2
x 2x 3 0
4
2
b b ac
x
a
2. output your labeled input and labeled results.
2- Temperatures may be converted from Celsius to Fahrenheit
using the formula
Write a program to input the temperature in Celsius and convert
it to Fahrenheit. Try your
program with C = -40°, C = 20°, and C = 100°.
(By the way, Excel have a conversion function called “convert”,
I urge you to search the help file
to learn more about it).
3- Polar coordinates are related to Cartesian Coordinates by the
following equations. Write a
program to input x = 2.5 and y = 7.1 to computer the r and θ.
Then input r = 5.5 and θ = 49° to
compute x and y.
2 2 1
cos( ) sin( ) tan ( )
y
x r y r r x y
x
3. ME209
CSUN-Mechanical Engineering Department
Homework # 1
A parachutist jumps from a stationary platform. Until the rip
cord is pulled, the jumper’s velocity can be
computed with the following equation:
( / ) ( / )
( ) (1 )d d
c m t c m t
o
d
gm
v t v e e
c
where v(t) is the downward velocity [m/s], v0 is the initial
4. downward velocity, t is time [s], g is the
gravitational acceleration constant [≈9.81 m/s2], m is the
jumper’s mass [kg], and cd is the drag coefficient
[kg/s], which parameterizes air resistance.
Develop an Excel workbook where the user can enter the mass,
the drag coefficient, initial velocity, and
end time. The user should be able to see the calculated velocity
of the time period [0,end_time] in table
and chart formats. Your submitted file should include:
1- Named Cells and Range
2- A properly created and labeled graph of velocity vs. time
(i.e. good graph as we discussed in
class).
3- Table shows the calculated velocity at each time step.
4- Discuss the behavior of the jumper’s velocity as the velocity
increase, i.e. as an engineer what
is the information you can extract from the equation above?
