microscopes

• how do you convert from cm to mm?

  x10
• how do you convert from mm to micrometres?

  x1000
• how do you convert from micrometres to nanometres?

  x1000
• what is magnification?


  the degree to which the size of an image is larger than the object itself. usually expressed numerically.
• what is resolution?


  the degree to which it is possible to distinguish between objects that are closer together. the higher the resolution the more detail.
• what is the calculation for magnification?

  size of image/actual size
• what is a light microscope?

  a microscope in which light rays are focussed onto a transparent specimen by a condenser lens which passes through the specimen.
• what are the advantages and disadvantages of a light microscope?

  advantages:cheap, colour, view live specimen, easy to use

  disadvantages:not a high resolution, low magnification
• what is a transmission electron microscope?

  a microscope where electron beams are bounced of the specimen which have shorter wavelengths compared to light rays
• what are the advantages and disadvantages of transmission light microscopes?

  advantages:high resolution and magnification

  disadvantages:only use on dead specimens, expensive, specimens have to be thin
• what is a scanning electron microscope?

  a microscope that bounces electron beams of surface of an object to give a 3 dimensional image
• what are the advantages and disadvantages of a scanning electron microscope?

  advantages:can see 3d, high magnification and resolution

  disadvantages:only produced in black white and grey, expensive, only use on dead specimens
• how do you work out calibration on a microscope?

  1. count stage lines

  2) count eye lines3) stage lines x 10micrometres4)answer/eyelines