grid and molecule and matter=p5/6

• What is the role of a fuse in an electrical circuit?


  • Protects appliances from excessive current.
  • Melts or blows if current exceeds a certain limit.
• What is the purpose of a step-up transformer?


  To increase the transmission voltage to reduce energy loss.
• What happens to the current when the voltage is increased in a step-up transformer?


  The current decreases.
• What happens when insulating materials are rubbed together?


  • Electrons are transferred from one material to another.
  • One object becomes positively charged, the other negatively charged.
• What is the equation for density?

  Density = mass / volume.
• How do you find the density of a regular object?


  By measuring its mass and volume, then using the density equation.
• What is the resolution of a vernier caliper?


  0.1 mm.
• How do you find the volume of an irregular object?


  By using water displacement method.
• What is the particle model of matter?


  • Describes how particles are arranged in solids, liquids, and gases.
  • Explains density and behavior of materials.
• What is the significance of electric fields?


  • Represent the force exerted by charged objects.
  • Direction is from positive to negative charges.
• What is the equation used to find density?

  Density = mass / volume
• Why are vernier calipers preferred over rulers for measuring small dimensions?


  Because vernier calipers have a resolution of 0.1 mm
• What is the resolution of a micrometer?


  0.01 mm
• How do we measure the volume of an irregular object?


  By using water displacement in a Eureka can
• What are the three main states of matter?

  Solid, liquid, and gas
• What happens to the particles of a solid when it melts?


  The particles gain kinetic energy and vibrate faster
• What is the melting point of ice?


  0° C
• Why does temperature remain constant during a change of state?


  Because energy is used to change potential energy, not kinetic energy
• What is the equation for increase in thermal energy?

  e = mcΔT
• What does specific latent heat (SLH) refer to?


  Energy needed to change the state of 1 kg of a substance
• What is the specific latent heat of fusion for water?


  334,000 J/kg
• How does heating a gas affect its pressure?


  It increases the pressure as particles move faster and collide more frequently
• What happens to pressure and volume at constant temperature?


  Pressure times volume equals a constant (P1V1 = P2V2)
• What are the units for pressure?

  Newtons per square meter (Pascals)