- STATION 6:DENSITY [4 marks] Sample: (1) A B Mass=0.02 Volume =underline ( ) Density =underline ( )
- The decibel scale, dB named after inventor Alexander Graham Bell, is also a logarithmic scale, measuring sound levels. The human ear can detect a very wide range of sounds, ranging from a soft whisper to loud machinery. The threshold of pain is about 1120 dB. Examples of other decibel measurements include normal conversation at about 50 dB, and a jet takeoff at about 140 dB The minimum intensity detectable by the human ear is I_(0)=10^-12W/m^2 (watts per square metre)and is used as the reference point.The sound level corresponding to an intensity / watts per square metre is: This formula can also be rewritten as: L=10log(1)/(1_(0)) I=10^(L)/(10)cdot I_(0) 8. Damage to the ear can occur with sound levels that are greater than or equal to 85 dB. Find the sound level of a rock concert with an intensity of 80W/m^2 to determine if fans at the concert are at risk for hearing damage. 9. Normal conversation has a sound level of 60 dB. A night club can have a sound level of 120 dB How many more times intense is the sound level at a night club compared to that normal conversation? 10 The noise in the library is 5000 times less intense than it is in the cafeteria. If the sound level is 80 dB in the cafeteria, what is the sound level in the library?
- 2. A2 .00 kg ball is dropped from the top of a 10.0 m high building. a. Calculate the potential energy AND kinetic energies at: 10 m
- STATION 6 DENSITY [4 marks] Sample: DA B Mass=000.02 Volume =underline ( ) Density =underline ( ) D=(m)/(v)
- 41 __ is an example of background radiation. a. Terrestrial b. Cosmic c. Artificial d. Both a b A B c D 42. One rem is equal to __ sieverts. a. 0.01 sv b. 15V c. 0.1 sv A B C 43. The use of the F-speed film instead of D-speed film reduces the absorbed dose by __ a. 10 b. 25 c. 50 d. 60 A B
