Answer:
The material stretched across the drum vibrates to produce the sound waves.
Explanation:
A drum is one of the oldest musical instrument made by man. It is made of a hollow body over which a material such as skin is stretched. When a drum is struck with a stick, the material vibrates up and down. This makes the air above the drum to contract and relax rhythmically resulting in soundwaves. The soundwaves travel through air to reach our ears where they are heard.
The quality of sound produced by a drum is affected by its shape. A larger drum produces a lower pitched sound.
Answer:
600 mC
Explanation:
The charge of an electron is 1.6 x 10-19C so for a current with 10 mA, the charge going to screen in one second is 10 mC
so number of electrons, n = (10 x 10-3)/(1.6 x 10-19) = 6.25 x 1016 so in a minute the charge is 10 * 60 = 600 mC
Answer: 757m/s
Explanation:
Given the following :
Mole of neon gas = 1.00 mol
Temperature = 465k
Mass = 0.0202kg
Using the ideal gas equation. For calculating the average kinetic energy molecule :
0.5(mv^2) = 3/2 nRt
Where ;
M = mass, V = volume. R = gas constant(8.31 jK-1 mol-1, t = temperature in Kelvin, n = number of moles
Plugging our values
0.5(0.0202 × v^2) = 3/2 (1 × 8.31 × 465)
0.0101 v^2 = 5796.225
v^2 = 5796.225 / 0.0101
v^2 = 573883.66
v = √573883.66
v = 757.55109m/s
v = 757m/s
f' = frequency observed by the police car after sound reflected from the vehicle and comes back to police car = 1250 Hz
f = frequency emitted by the police car = 1200 Hz
V = speed of sound = 340 m/s
v = speed of vehicle = ?
frequency observed by the police car is given as
f' = f (V + v)/(V - v)
inserting the values in the above equation
1250 = 1200 (340 + v)/(340 - v)
v = 6.9 m/s
