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With each contraction of the heart, there is a redistribution of electric charge forming an electric dipole in the heart. -. +. Estimate the direction of the net electric force on a Sodium ion (Na+) and on a chlorine ion (Cl-) at the position of the dot above. Net Force. Net Force. -. +. -.
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With each contraction of the heart, there is a redistribution of electric charge forming an electric dipole in the heart. - + Estimate the direction of the net electric force on a Sodium ion (Na+) and on a chlorine ion (Cl-) at the position of the dot above.
Net Force Net Force - + - + Cl- Na+
A new idea has been proposed to launch rockets into orbit without using gasoline. The launching involves charged objects and a strong spring. Initial Final + v > 0 h >> 0 + + + + + + + v = 0 h = 0 + + + + + + + + + + + + + + Construct an Energy Bar Chart of this situation. Be sure to state what assumptions you made.
One of many choices. Note the four energies shown below and that the heights on the left equal the heights on the right. KoPEgoPEqoPEso W KPEgPEqPEs DEint 0 • Assumptions: • Rocket is far enough away so PEq is basically zero. • No energy loss due to resistive frictional forces. • Spring is initially compressed.
A small cart with a charged sphere on top is located exactly between two fixed charged plates. -q +q +q x x + + - + + + Construct a free body diagram at the instant the cart is released and a motion diagram for the cart.
Free Body Diagram Motion Diagram • Assumptions: • Cart has no initial velocity • Surface is frictionless
A small cart with a charged sphere on top is located exactly between two fixed charged plates. It has a velocity towards the right. v +q +q -q x x + + - + + + Construct a free body diagram for the cart at the instant it is at the midpoint and an approximate motion diagram.
Free Body Diagram • Assumptions: • Surface is frictionless
A small cart with a charged sphere on top is located between two fixed charged plates. +q +q -q 2 x x + + - + + + Construct a free body diagram for the cart at the instant the cart is released and a motion diagram
Free Body Diagram Motion Diagram • Assumptions: • Cart has no initial velocity • Acceleration is NOT constant • Fleft charge on cart is 1/4th of Fright charge on cart
A process is described with the bar chart below. KoPEgoPEqoPEso W KPEgPEqPEs DEint 0 Describe this process with words and a picture for one possible scenario.
A small cart has a negatively charged sphere on top. The positive charge exerts a net force on the sphere to pull it towards the right. The electrical potential energy decreases (becomes more negative) as the kinetic energy and internal thermal energy due to friction increases. +q -q - + + • Assumptions: • Horizontal surface that has friction
Water is flowing from a faucet as shown below. + A positively charged rod is brought close to the stream of water. Construct a picture of this situation and describe in words what is happening.
- + - + - + - + - - + - + + The rod is brought close to the water. This causes the polar water molecules to orientate themselves such that the negative sides of the dipole are more towards the rod and the positive sides are away. This positive rod then exerts an electro-static force on the water, causing it to bend.