Total # Posts: 25
apparent change in wavelength of sound waves is 2.5cm when the source of sound is approaching stationary listener with velocity 8cm/s.Apparent decrease in the frequency of source when observer recedes from the same source at rest with a velocity of 30m/s is (velocity of sound...
April 6, 2016
A weight lifter is raising a barbell of mass 120kg. He does this in two stages. At the end of the first stage he holds the barbell steady at shoulder height. What upward force is each arm exerting?
October 25, 2013
mary has 12 marbles 3/12 of the marbles are yeallo and 2/12 of the marbles are blue . the rest of the marble are green . how many marbles are green ? explain how you know ?
February 26, 2013
al mustafa publick school
two planets of masses m and respectively.have a centre to center separation of r.at what distance from the center of the pianet of mass m do the gravitational force of planets cancel each other???
May 4, 2012
A dam 15 m high holds the water in reservoir . For safety reasons , the water level is maintained at a height 3 m below the top of the dam. At best of the dam , engineers have installed a vertical door in the shape of an equilateral triangle with sides of length 3 m , ...
January 30, 2011
1. Suppose a certain instructor is interested in determining the average final grade for all students taking STA 205 in any given semester. Suppose she obtains the academic records for 100 former STA 205 students. For this scenario, determine both the population and the sample...
January 18, 2011
Boyle's law states that if the temperature of a gas remains constant, then PV = c. Where P is the pressure, V is the volume, and c is a constant. Given a quantity of gas at constant temperature, if V is decreasing at a rate of 13 in.^3/s, at what rate is P increasing when ...
May 2, 2010