- #1
zell_D
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Homework Statement
1. A woman weighing 730N stands in the middle of a frozen pond of radius 5m. She is unable
to get to the other side because of a lack of friction between her shoes and the ice. To propel
herself, she throws a 1.2kg backpack horizontally towards the south shore at a speed of 5m/s.
How long does it take her to reach the north shore?
2. Two blocks are in contact on a frictionless surface., sitting horizontally next to each other. You apply a force of 3.2N to block 1 such that it pushes against block two. Mass of block 1 = 3.2kg. Mass of block 2 = 1.2 kg. What is the magnitude of the force between the two blocks?
3.The density of bubble gum is about 1g per cubic cm. You blow an 8g wad of gum into a
bubble with a 10cm diameter. What is the thickness of the bubble's skin?
Homework Equations
1. conservation of momentum (explosion?) (Mass A + Mass B)V initial = Mass A*V A + Mass B * V B?
2. F=ma F=0
3. no idea? 4/3pi r^3?
The Attempt at a Solution
I did number 1, my answer came out to be something like 62.07 seconds but i am not sure if its right. Need someone to check for me. (I set the initial velocity to zero since the backpack on the woman AND the woman were in the middle of the pond not moving right?)
number 2 and 3 i have no idea, i drew the diagrams out but does the box being pushed on have a normal force pushing back or no?
number 3 i just have absolutely NO idea lol