You must assume that the mass of the rocket and engine remains constant - even though the engine is burning.
You know the engine produces 13.8N for a distance of 14.6m
The total energy expended (work done) by the engine is FxD so you can calculate that
Now - some of that is given to the rocket as kinetic and potential energy, and some is expended against the drag force.
At the peak of its flight ALL the energy given to the rocket is potential energy (its velocity is zero) and that is calculated as mgh
So
Energy given to rocket = mgh
Energy expended by engine = F x D (D= height where engine stops)
Energy 'lost' to drag is the difference between the two values.
Answer:
a) iv. Displacement per unit time
b) ii. m/s2
c) this question is wrong
d) iv. m
Answer:
Wh en an ele ctric c urrent flows in a wire, it cre at es a ma g ne tic fie ld around the wire. Thi s ef fect can be used to make an electromagnet . A simple electr om agnet a length of wire tur ned into a c oil an d co nnected to a batt e ry or po wer sup ply.
Explanation:
Answer:


Explanation:
m = Mass of electron = 
B = Magnetic field = 0.22 T
K = Kinetic energy of electron = 
q = Charge = 
v = Velocity of electron
r = Radius of curved path
Kinetic energy is given by

The speed of the electron is 
The force balance of the system is given by

The radius of the curved path is 
Answer:
The second distance of the sound from the source is 431.78 m..
Explanation:
Given;
first distance of the sound from the source, r₁ = 1.48 m
first sound intensity level, I₁ = 120 dB
second sound intensity level, I₂ = 70.7 dB
second distance of the sound from the source, r₂ = ?
The intensity of sound in W/m² is given as;
![dB = 10 Log[\frac{I}{I_o} ]\\\\For \ 120 dB\\\\120 = 10Log[\frac{I}{1*10^{-12}}]\\\\12 = Log[\frac{I}{1*10^{-12}}]\\\\10^{12} = \frac{I}{1*10^{-12}}\\\\I = 10^{12} \ \times \ 10^{-12}\\\\I = 1 \ W/m^2](https://tex.z-dn.net/?f=dB%20%3D%2010%20Log%5B%5Cfrac%7BI%7D%7BI_o%7D%20%5D%5C%5C%5C%5CFor%20%5C%20120%20dB%5C%5C%5C%5C120%20%3D%2010Log%5B%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5D%5C%5C%5C%5C12%20%3D%20%20Log%5B%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5D%5C%5C%5C%5C10%5E%7B12%7D%20%3D%20%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5C%5C%5C%5CI%20%3D%2010%5E%7B12%7D%20%5C%20%5Ctimes%20%5C%2010%5E%7B-12%7D%5C%5C%5C%5CI%20%3D%201%20%5C%20W%2Fm%5E2)
![For \ 70.7 dB\\\\70.7 = 10Log[\frac{I}{1*10^{-12}}]\\\\7.07 = Log[\frac{I}{1*10^{-12}}]\\\\10^{7.07} = \frac{I}{1*10^{-12}}\\\\I = 10^{7.07} \ \times \ 10^{-12}\\\\I = 1 \times \ 10^{-4.93} \ W/m^2](https://tex.z-dn.net/?f=For%20%5C%2070.7%20dB%5C%5C%5C%5C70.7%20%3D%2010Log%5B%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5D%5C%5C%5C%5C7.07%20%3D%20%20Log%5B%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5D%5C%5C%5C%5C10%5E%7B7.07%7D%20%3D%20%5Cfrac%7BI%7D%7B1%2A10%5E%7B-12%7D%7D%5C%5C%5C%5CI%20%3D%2010%5E%7B7.07%7D%20%5C%20%5Ctimes%20%5C%2010%5E%7B-12%7D%5C%5C%5C%5CI%20%3D%201%20%5Ctimes%20%5C%2010%5E%7B-4.93%7D%20%5C%20W%2Fm%5E2)
The second distance, r₂, can be determined from sound intensity formula given as;

Therefore, the second distance of the sound from the source is 431.78 m.