The Hooke's law is a principal of physics that states that the force needed to extend or compress a spring by some distance x scales linearly with respect to that distance.
Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = () · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f = · 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
If there is no friction, the force that moves the box forward horizontally must be matched by the same force.
If there is friction, then the force moving it forward = frictional force + the additional force you need to add.
The question is somewhat ambiguous.
-- It's hard to tell whether it's asking about '3 cubic meters'
or (3m)³ which is actually 27 cubic meters.
-- It's hard to tell whether it's asking about '100 cubic feet'
or (100 ft)³ which is actually 1 million cubic feet.
I'm going to make an assumption, and then proceed to
answer the question that I have invented.
I'm going to assume that the question is referring to
'three cubic meters' and 'one hundred cubic feet' .
OK. We'll obviously need to convert some units here.
I've decided to convert the meters into feet.
For 1 meter, I always use 3.28084 feet.
Then (1 meter)³ = 1 cubic meter = (3.28084 ft)³ = 35.31 cubic feet.
So 3 cubic meters = (3 x 35.31 cubic feet) = 105.9 cubic feet.
That's more volume than 100 cubic feet.
It IS <span>PE = (1200 kg)(9.8 m/s²)(42 m) = 493,920 J </span>