Isolated bells ring clear, while bells crammed in a box have a muffled ring. if the sound of isolated bells is analogous to light from a gas discharge tube, then sound from the box crammed with bells is analogous to light from group of answer choices

1. a phosphorescent source.
2. none of these
3. an incandescent lamp.
4. a fluorescent lamp.
5. a laser.

69. air frictionthe velocity of the satellitea. decreases b. increases c. sometimes increases sometimedecreases d. no effect at all70. the unit of gravitational potential energy isa.jouté b.watt c. newtond.pascal71. which of the following is not influenced by a magneta. cobalt b.copper c.irond. nickel72. one joule of work done in one second by unit positive chargea.1 watt b.1 volt c.1 js d. none73. the most deviated colour of light after passing through a prisea. violet b.red c. green d.yellow4. a coin is placed below a beaker fill with water upto 12 cm isdisplaced by water isa. 9cm b.6cmс.3cmd.7cm