Recent content by Angela Liang

  1. A

    Can More Readings Reduce Fractional Error in Measurement?

    Why is fractional uncertainty not affected by systematic error? For example à vernier calipers measures the diameter of a coin: (5.06+-0.04) mm Can taking more readings, say 6, and taking average, reduce fractional error?
  2. A

    What’s the relation between activity and half-life

    I’m confused because there are two equations: 1) A=λN 2) A=A0exp^-(λt)If half-life increases, λ decreases, and A decreases according to 1); but, If half life increases, λ decreases, hence exp^-(λt) decreases, A should decreases according to 2)Why is this so? Where went wrong? Thanks!
  3. A

    Understanding the Relationship Between Potential Energy and Direction in Fields

    Oh yea I got what you mean. Closer field lines means stronger field. Thanks!
  4. A

    Understanding the Relationship Between Potential Energy and Direction in Fields

    Thanks! But why does the force increase and then decrease?
  5. A

    Understanding the Relationship Between Potential Energy and Direction in Fields

    Why do we not need to consider direction when determining the change in potential energy? Why do we need to consider it in case of force? Or am I interpreting the question correctly?
  6. A

    B Velocity of Sphere Falling from Rest in Oil-Filled Beaker

    Hi! I'm thinking how would the velocity of a sphere change if it falls from rest in a tall beaker full of oil. I know that the direction of acceleration is upwards, and the acceleration should be decreasing at a decreasing rate. But how would the velocity change if the velocity is initially zero...
  7. A

    When does potential energy change?

    Thank you very much:)
  8. A

    When does potential energy change?

    There is a fixed mass of gas. By increasing the volume, the internal energy doesn't change. So does the temperature change? Cos in my understanding, internal energy= internal KE + internal PE. Does increasing the volume increase the PE of the particles? If so, the internal KE should have...
  9. A

    When does potential energy change?

    Thanks. How to describe it using kinetic model of matter?
  10. A

    When does potential energy change?

    How about gas in an enclosed system?
  11. A

    When does potential energy change?

    Why doesn't the potential energy of a substance change when the pressure changes? Or in what case will the potential energy of a substance change?
Back
Top