- #1
rvhockey
- 11
- 0
1. Which rolls to the bottom of a hill sooner, a car tire alone or the same tire mounted on a rim?
a. The mounted tire, provided the tire is more massive than the rim
b. The tire alone, provided it is as heavy as the rim
c. The mounted tire, provided the tire is as heavy as the rim
d. The tire alone, regardless of its weight
e. The mounted tire, regardless of its weight
2. A ring and a disk roll down a hill together. Which reaches the bottom first?
a. Both reach the bottom at the same time
b. Depends on the moments of inertia
c. The disk
d. Depends on the masses
e. The ring
3. A ring, a disk, and a solid ball having equal masses roll down a hill at the same time. Which reaches the bottom first?
a. Depends on what each is made of
b. The disk
c. The ring
d. Depends on the radius of each
e. The ball
The only ones I'm using are
Iring = MR2
Icyclinder = (1/2)MR2
Isphere = (2/5)MR2
For number 1, my teacher said it wasn't d, so I have it down to e, because a cyclinder (mounted tire) has a smaller rotational inertia.
For number 2, my teacher said it wasn't b, so I'm thinking its c because of the cyclinder again.
For number 3, my teacher said it wasn't d, and I have no clue what else it could be, because if the radii are different enough, can't all the inertias be equal?
Any thoughts would be greatly appreciated
a. The mounted tire, provided the tire is more massive than the rim
b. The tire alone, provided it is as heavy as the rim
c. The mounted tire, provided the tire is as heavy as the rim
d. The tire alone, regardless of its weight
e. The mounted tire, regardless of its weight
2. A ring and a disk roll down a hill together. Which reaches the bottom first?
a. Both reach the bottom at the same time
b. Depends on the moments of inertia
c. The disk
d. Depends on the masses
e. The ring
3. A ring, a disk, and a solid ball having equal masses roll down a hill at the same time. Which reaches the bottom first?
a. Depends on what each is made of
b. The disk
c. The ring
d. Depends on the radius of each
e. The ball
The only ones I'm using are
Iring = MR2
Icyclinder = (1/2)MR2
Isphere = (2/5)MR2
For number 1, my teacher said it wasn't d, so I have it down to e, because a cyclinder (mounted tire) has a smaller rotational inertia.
For number 2, my teacher said it wasn't b, so I'm thinking its c because of the cyclinder again.
For number 3, my teacher said it wasn't d, and I have no clue what else it could be, because if the radii are different enough, can't all the inertias be equal?
Any thoughts would be greatly appreciated