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  Adam's Brunoise Dice - $5 Physics Quiz

  Adam's Brunoise Dice - $5 physics quiz
   
  
  Adam Petropoulos recently got admitted to the culinary institute named Le Monde in Athens, Greece. His career goal was to become a chef.  He loved food!  He wanted to learn the art of flavor...

  • June 21, 2021

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    Khadeeza Afruz Shammee Pascal's principle of pressure describes this knife phenomenon. As a scalar physical quantity ,pressure is defined as the force per unit area applied perpendicular to the surface which it is applied .
    The elementary mathematical expression for pressure...  morePascal's principle of pressure describes this knife phenomenon. As a scalar physical quantity ,pressure is defined as the force per unit area applied perpendicular to the surface which it is applied .
    The elementary mathematical expression for pressure is giving by ,
    P = F/A
    Here, P is the pressure , F is the force acting perpendicular to the surface to which this force is applied and A is the area of the surface .
    The same force applied by a sharp knife with a smaller area of contact will exerts a much greater pressure than a blunt knife having a considerable larger area of contact .
    Once a blunt knife is through the object (vegetable or other food), there is a greater chance for the pressure to lead to slippage, skidding and injury. A sharp knife can cut using the edge of the e knife with a safer slicing. Rather, cuts from sharper knives can actually heal more easily than those from dull knives. A sharp knife is a safer knife than a dull knife.  less

    • June 25, 2021
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    Aria Hossain In physics force=pressure/area. In order to cut food, you have to exert force. According to the equation, force is directly proportional to pressure. A blunt knife has more area around the cutting edge than a sharp knife. So a blunt knife requires more...  moreIn physics force=pressure/area. In order to cut food, you have to exert force. According to the equation, force is directly proportional to pressure. A blunt knife has more area around the cutting edge than a sharp knife. So a blunt knife requires more pressure for the same amount of force to be exerted, as the pressure applied increases the chances of the knife slipping and cutting Adam's hand increases. Similarly, a sharp knife would require less pressure to be applied for the same amount of force to be exerted, this not only allows Adam to cut through the food but also prevents the knife from slipping and cutting his hand.  less

    • June 26, 2021
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    Abdullah Julaybib Firstly, you’ll need more pressure to use a blunt knife.
    P=F/A, for a fixed area, force is directly proportional to pressure. If the
    area of a blunt and a sharp knife is same, then doubling the pressure on blunt
    knife means doubling the force....  moreFirstly, you’ll need more pressure to use a blunt knife.
    P=F/A, for a fixed area, force is directly proportional to pressure. If the
    area of a blunt and a sharp knife is same, then doubling the pressure on blunt
    knife means doubling the force.
    
    Secondly,F= {m(v-u)}/t
    
    Assume, two knives have same mass and you take same amount of time to cut. As
    you start from a zero velocity, that means u=0. Ultimately you end up giving
    much more velocity to the blunt than sharp one. So, if you accidentally slip
    while cutting, blunt will hit your finger faster, which might cause a serious
    injury. Sharp knife will have less velocity, which has multiple advantages:
    bringing the sharp knife to rest is easier than blunt one. If you slip, sharp
    knife won’t hit so fast. It may cause a
    little scratch, or you’ll be lucky to stop the sharp knife as soon as it touches your skin (blunt one
    would cause a deep scar).
    
    
    For same time duration, point of contact (finger and knife)
    faces two different momenta. As a result,...    less

    • June 26, 2021
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    Abhay Sunny Pressure= force/area, area of sharp knife is less than area of blunt knife, p is proportional to 1/area, so pressure of sharp knife is more than blunt knife.Don't get confused with the wight and pressuring, pressure is the force on a unit area that is...  morePressure= force/area, area of sharp knife is less than area of blunt knife, p is proportional to 1/area, so pressure of sharp knife is more than blunt knife.Don't get confused with the wight and pressuring, pressure is the force on a unit area that is help perpendicular whereas weight is the force by which the earth attracts everything towards it's center.  

    • June 27, 2021
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    Abdullah Masud This is simply an example of pressure in our daily lives. Here, according to Pascal's law (P = f/a, where pressure is the force applied over a certain area), the sharp knife can exert greater pressure than the blunt knife, as the sharper knife has less...  moreThis is simply an example of pressure in our daily lives. Here, according to Pascal's law (P = f/a, where pressure is the force applied over a certain area), the sharp knife can exert greater pressure than the blunt knife, as the sharper knife has less contact area for the same force than the blunt knife, so the force would be exerted over a smaller area. So in order to cut anything, one would need to apply a larger force in a blunt knife than a sharper knife, and this might result in the blunt knife cutting the hand due to excessive pressure applied by the user while cutting any other objects.  less

    • June 27, 2021
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  Abrar Ibne Amin Jim joined the group Coolinventor Contributors

  • June 13, 2021
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  Abrar Ibne Amin Jim commented on Fatima Ahmed's classified listing.

  

  Jacob's Alaskan Trip

  Jacob's Alaskan Trip
   
  
  Jacob was a physics student at the University of Texas in Austin, Texas, USA.  His hometown was a small city called Soldotna in the Kenai Peninsula in the US state of Alaska. Soldotna's winter was extremely cold w...

  • June 13, 2021

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    Tanveer Tausif Ratul The 1st phenomena is the result of "friction" which opposes the vehicle's tyre rubber from sliding on slippery roads.The tread on the tires gripped the road surface while jacob was driving and from common sense,it can be realized that jacob's...  moreThe 1st phenomena is the result of "friction" which opposes the vehicle's tyre rubber from sliding on slippery roads.The tread on the tires gripped the road surface while jacob was driving and from common sense,it can be realized that jacob's car had winter tyres which have deeper tread.The treads grip the ice well enough & larger frictional force is produced there as the area of contact becomes larger.Treads have certain patterns that push
    away the ice and snow.So he could drive safely.If no tread, there will be less friction and driving will become unsafe.
    
    Jacob's shoes slipped because uppermost ice layer contains thin water layer on it.Deeper ice layers stick to each other well but upper layers are very loose as they always remain in contact with air.While walking, jacob's shoes rubbed on ice that caused friction.Friction created heat and heat helped to melt the ice which made it more slippery.
    Frictional force is produced where there is a kinetic force acting between the two...    less

    • June 13, 2021
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    Tanveer Tausif Ratul objects.When Jacob was rubbing his hand,a frictional force was produced which was emitted as heat.That energy didn't not come from the atmosphere, but rather the energy he was spending to overcome the frictional forces.

    • June 13, 2021
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    Abrar Ibne Amin Jim All the situations described above hints at Newton’s 3rd Law & specifically Frictional force.
    
    1) Situation-1, Jacob’s car could travel the road despite the road was slippery. This happened as the tires had enough grooves to increase friction....  moreAll the situations described above hints at Newton’s 3rd Law & specifically Frictional force.
    
    1) Situation-1, Jacob’s car could travel the road despite the road was slippery. This happened as the tires had enough grooves to increase friction. Friction increases due to rough surface, so the tires could make a firm grip on the road and prevent slipping. But if the tires hadn’t enough groove it could felt due to the smooth icy road.
    
    2) 2nd situation where Jacob slipped on the ground due to wearing regular shoes. Although static friction occurred it wasn’t enough to stop slipping as the shoes of Jacob didn’t have enough grip to increase friction.
    
    3) We can see in the 3rd situation that through rubbing his palms together, Jacob felt warm on both palms. This occurred due to sliding friction. The molecules in the palms of Jacob’s started moving quickly. Static electricity was produced due to the sliding friction. Thus this static electricity converted into heat energy. So friction is the root of this.  less

    • June 13, 2021
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    Abdullah Masud In his wonderful journey, he has met some of the interesting and fundamental laws of physics. First of all, it can be noticed that surface of the ice is slippery. So in order to prevent skidding, the tire of the car had a grooved pattern moulded into the...  moreIn his wonderful journey, he has met some of the interesting and fundamental laws of physics. First of all, it can be noticed that surface of the ice is slippery. So in order to prevent skidding, the tire of the car had a grooved pattern moulded into the rubber surface and are properly inflated which increases the amount of friction force acting on the car and so the car can move smoothly through the ice. Secondly, it is quite good to mention that normal shoes are not built to create a lot of frictional force, so as the ice is slippery, due to less frictional force, Mr Jacob slips.
    In order to prevent slipping on ice, ice boots have quite a good surface that can create a lot of friction with the ice, preventing the user of the boots from sleeping. Thirdly, rubbing hands is also an example of friction. Rubbing hands allows surfaces from both the hands to come into contact and rub against each other and this movement causes friction force to convert the kinetic energy of the hands into the thermal...    less

    • June 13, 2021
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    Shafaat Shams 1. The snowy road
    is so slippery and doesn’t have enough grips. Jacob’s Car was useful there; it
    gives power to all 4 wheels at the same time. With the help of heavy car
    weight, those 4 tires made 4 friction points. The more friction it made,...  more1. The snowy road
    is so slippery and doesn’t have enough grips. Jacob’s Car was useful there; it
    gives power to all 4 wheels at the same time. With the help of heavy car
    weight, those 4 tires made 4 friction points. The more friction it made, the
    more grip the car got. He might use frictional tires for getting more grips. In
    consequence of that, he moved easily.
    
    
    2.
    On the ice, there are
    unstable water molecules that are weakly bonded to the crystal. When Jacob
    walked on ice, the molecules began to move freely. His shoes had not enough
    friction point to grip in ice. As a result, his foot did not get enough static
    friction force to hold him in place & he slipped.
    
    
    3.
    Jacob’s hands came in contact & move relative to each
    other; the friction between the two hand surfaces converts kinetic energy into
    thermal energy. Thermal energy made his hand wormer and made it safe from being
    frozen.  less

    • June 14, 2021
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  • June 13, 2021