The relationship between the frequency heard by the observer in motion and the original frequency of the sound is given by (Doppler effect)
where
f' is the frequency heard by the observer
v is the speed of the wave (the speed of sound)
is the speed of the source relative to the observer (= the speed of the car), and it is negative when the source is approaching the observer
f is the original frequency of the sound
By re-arranging the formula, we get
and by plugging the data of the problem into the equation, we find
so, the car is approaching the observer at 15.2 m/s.
Answer:
force exerted by the cat is 693 N
Explanation:
We know that total energy is the sum of work done by gravity and friction i.e.
solving for F
here -ve sign indicate work done in opposite direction
where, m is mass of cat = 4.00 kg
h = 2.00 m, 
Putting all value in above equation
F = 692.53 N = 693 N
Therefore force exerted by the cat is 693 N
Answer:im thinking like 1000000000000000000000 trees they sold or maybe this amount 10000
Explanation:
Answer:
Explanation:
ME initial = ME final
PE initial + KE initial = PE final + KE final
There's no kinetic energy the moment Jorge is at the top of the ramp therefore KE initial = 0
PE initial = PE final + KE final
Assuming the bottom of the ramp is h = 0 we can then say PE final = 0
PE initial = KE final
Write the equations out.
mgh = (.5)mv^2
They tell us potential energy is 6000J therefore that portion of the equation is already "solved"
6000 = (.5)mv^2
Plugin the values
6000 = (.5) 70 v^2
Solve for v
6000 = 35v^2
171.43 = v^2
13.1 = v at the bottom of the slope
Solving for KE we get
(.5) m v^2
Plugin the value from the previous problem and solvee!
Well you didnt give us any options to choose from
but my guess is that it has to do with erosion caused by the water
