Explanation:
Given that,
Weight of the engine used to lift a beam, W = 9800 N
Distance, d = 145 m
Work done by the engine to lift the beam is given by :
W = F d

Let W' is the work must be done to lift it 290 m. It is given by :

Hence, this is the required solution.
Answer:
(A) 7.9 m/s^{2}
(B) 19 m/s
(C) 91 m
Explanation:
initial velocity (U) = 0 mph = 0 m/s
final velocity (V) = 85 mph = 85 x 0.447 = 38 m/s
initial time (ti) = 0 s
final time (t) = 4.8 s
(A) acceleration = 
=
= 7.9 m/s^{2}
(B) average velocity = 
=
= 19 m/s
(C) distance travelled (S) = ut + 
= (0 x 4.8) +
= 91 m
So, option 3 or the ambulance sound waves have more waves and shorter wavelength is the correct reason for ambulance siren having higher pitch compared to fire truck siren
Explanation:
Pitch of any sound wave is determined as the clarity in frequency of notes or the number of times a cycle is repeated for a single second. So pitch is similar to frequency. And frequency is the measure of number of complete cycles in a second. So if the ambulance siren has higher pitch compared to siren of fire truck. Then this means the frequency of ambulance siren is greater than the fire truck siren. As the frequency is more, then from the given options, choice 3 is correct. The ambulance siren have more waves and shorter wavelength. As more the frequency or number of waves, lesser or shorter is the wavelength of sound wave from ambulance.
The goal of scientific method is to produce public knowledge. That is knowledge available to any person with sufficient education, all such knowledge can be verified by or deduced from experiments and observations.
Hi Jason!☺
The answer is going to be
B, they harm the ozone layer.I have taken the quiz and am 100% sure.
~Elisabeth