PHYS 220 (Purdue) Exam Questions with Verified
Answers |2026/2027 Update | A+ Graded
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
relative to the ground? - Answer -+2 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
at the bottom of the wheel relative to the ground? - Answer --2 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
of the top of the wheel relative to the ground? - Answer -+4 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
of the bottom of the wheel relative to the ground? - Answer -0 m/s
You decide to roll two objects down a ramp to see which one gets to the bottom first. Object A
is a solid cylinder and object B is a hollow cylinder. A and B have the same mass and radius.
Suppose you released them from rest at the top of the ramp at same time, which has the most
kinetic energy when it gets to the bottom of the ramp? - Answer -Same
1|Page
, A hoop and a cylinder of equal mass roll down a ramp with height h. Which has greater speed at
the bottom of the ramp? - Answer -Cylinder: Cylinder will get to the bottom first because inertia
for a cylinder is less than that for a hoop type object.
Which contains more atoms ? - Answer -A mole of water (H2O)
Which weighs more ? - Answer -A mole of oxygen gas (O2): O2 (M=16+16)
Two cups of coffee are heated to 100 degrees Fahrenheit. Cup 1 is then heated an additional 20
degrees Centigrade, cup 2 is heated an additional 20 Kelvin. Which cup of coffee is hotter? -
Answer -They are the same: K = C + 273
You measure your body temperature with a thermometer calibrated in Kelvin. What do you
hope the reading is (assuming you are not trying to fake some sort of illness) ? - Answer -310 K
You inflate the tires of your car so the pressure is 30 psi, when the air inside the tires is at 20
degrees C. After driving on the highway for a while, the air inside the tires heats up to 38 C.
Which number is closest to the new air pressure? - Answer -32psi:Careful, you need to use the
temperature in K P = P0 (38+273)/(20+273)
What happens to the pressure of the air inside a hot-air balloon when the air is heated?
(Assume V is constant) - Answer -Same: Balloon is still open to atmospheric pressure, so it stays
at 1 atm
2|Page
Answers |2026/2027 Update | A+ Graded
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
relative to the ground? - Answer -+2 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
at the bottom of the wheel relative to the ground? - Answer --2 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
of the top of the wheel relative to the ground? - Answer -+4 m/s
A wheel is spinning clockwise such that the speed of the outer rim is 2 m/s. What is the velocity
of the bottom of the wheel relative to the ground? - Answer -0 m/s
You decide to roll two objects down a ramp to see which one gets to the bottom first. Object A
is a solid cylinder and object B is a hollow cylinder. A and B have the same mass and radius.
Suppose you released them from rest at the top of the ramp at same time, which has the most
kinetic energy when it gets to the bottom of the ramp? - Answer -Same
1|Page
, A hoop and a cylinder of equal mass roll down a ramp with height h. Which has greater speed at
the bottom of the ramp? - Answer -Cylinder: Cylinder will get to the bottom first because inertia
for a cylinder is less than that for a hoop type object.
Which contains more atoms ? - Answer -A mole of water (H2O)
Which weighs more ? - Answer -A mole of oxygen gas (O2): O2 (M=16+16)
Two cups of coffee are heated to 100 degrees Fahrenheit. Cup 1 is then heated an additional 20
degrees Centigrade, cup 2 is heated an additional 20 Kelvin. Which cup of coffee is hotter? -
Answer -They are the same: K = C + 273
You measure your body temperature with a thermometer calibrated in Kelvin. What do you
hope the reading is (assuming you are not trying to fake some sort of illness) ? - Answer -310 K
You inflate the tires of your car so the pressure is 30 psi, when the air inside the tires is at 20
degrees C. After driving on the highway for a while, the air inside the tires heats up to 38 C.
Which number is closest to the new air pressure? - Answer -32psi:Careful, you need to use the
temperature in K P = P0 (38+273)/(20+273)
What happens to the pressure of the air inside a hot-air balloon when the air is heated?
(Assume V is constant) - Answer -Same: Balloon is still open to atmospheric pressure, so it stays
at 1 atm
2|Page
