Answer: The frequency = 1714.3Hz
Explanation: The solution can be achieved by using doppler effect formula.
Since the source is moving toward the observer, the velocity of the observer will be positive.
Please find the attached file for the solution
Wavelength can be calculated using the following formula: wavelength = wave velocity/frequency. Wavelength usually is expressed in units of meters.
There was no net force on the stuffed toy, because the kids might have the same strength, The same force is on both sides of it. T<span>hey cancel each other out. They exert a force on the stuffed toy equal in strength but opposite in direction. The forces are balanced and the stuffed toy does not move. </span>Its like a game of tug-o-war, but you and I have the same strength. the rope would be still and not moving.
The sound is increased because sound waves are in fact mech. waves which means the that they can't travel through empty space and thus need a medium to travel through
Answer:
1) 50 seconds 2) 100°C
Explanation:
(Follows formula of Power=Energy/Time)
1) 500W x X = 2000J/kg°C x .25kg x 50°C
X = 50 seconds.
2) 2000W x 300s = 1000J/kg°C x 2kg x X
X = 300
Initial temperature => 400°C-300°C = 100°C