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A wave is modeled with the function y(x,t) = (0.66m) cos((0.03rad/m)x − (0.9rad/s)t + π/3). Find the wavelength.
Round your answer to 2 decimal places.
Do not forget the unit
3. A psychologist believes that it will take at least an hour for certain disturbed
children to learn a task. A random sample of 30 of these children results in a
mean of 50 minutes to learn the task. Should the psychologist modify her belief
at the 0.01 level if the population standard deviation can be assumed to be 15
minutes?
2. A light-bulb manufacturer regularly advertises that his bulbs last 900 hours
with a standard deviation of 75 hours. A random sample is chosen before each
campaign to make sure that the claim is correct. If one such sample of 20 bulbs
show a mean of 925 hours, can the advertising claim be considered an
underestimate at the 0.05 level of significance?
A wave is modeled with the function y(x,t) = (0.58m) cos((0.21rad/m)x − (0.03rad/s)t + π/3). Find the wave speed.
Round your answer to 2 decimal places.
Do not forget the unit
Transverse waves travel through a string where the tension equals 14.58 N with a speed of 20.61 m/s. What tension would be required for a wave speed of 25.36 m/s?
Round your answer to 2 decimal places.
Do not forget the unit
1. According to the norms established for a history test, grade eight students
should have an average 81.7 with a standard deviation of 8.5. If 100 randomly
selected grade eight students from a certain school district average 79.6 in this
test, can we conclude at the 0.05 level of significance that grade eight students
from this school district can be expected to average less than the norm of 81.7?
What is the wavelength of an earthquake that shakes you with a frequency of 33 Hz and gets to another city 95 km away in 20.6 s?
Round your answer to 0 decimal places.
Do not forget the unit
A string is 6.17 m long with a mass of 3.37 g. The string is held taut with a tension of 448 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
Round your answer to 5 decimal places.
Do not forget the unit
A pendulum that has a period of 7.01 s and that is located where the acceleration due to gravity is 9.44 m/s2 is moved to a location where the acceleration due to gravity is 9.31 m/s2. What is its new period?
Round your answer to 5 decimal places.
Do not forget the unit
Calculate the entropy change of freezing of 20.0 g liquid metal mercury at -38.9°C (molar enthalpy of fusion of mercury is 2.33kJ/mol)
