15+3=18km/hour
Think about it like this. The boat is going 15 faster than the river, and the river is going 3 faster than the bank, so the boat is going 18 faster than the river bank
The trachea is a tube that carries air inside the lungs.
Answer:
Explanation:
Given
length of wire 
change in length 
mass of wire 
Young's modulus for silver 
load on wire 

change in length is given by

Where A=area of cross-section




also wire is the shape of cylinder so cross-section is given by





Answer:
the density of mobile electrons in the material is 3.4716 × 10²⁵ m⁻³
Explanation:
Given the data in the question;
we make use of the following expression;
hall Voltage VH = IB / ned
where I = 2.25 A
B = 0.685 T
d = 0.107 mm = 0.107 × 10⁻³ m
e = 1.602×10⁻¹⁹ C
VH = 2.59 mV = 2.59 × 10⁻³ volt
n is the electron density
so from the form; VH = IB / ned
VHned = IB
n = IB / VHed
so we substitute
n = (2.25 × 0.685) / ( 2.59 × 10⁻³ × 1.602×10⁻¹⁹ × 0.107 × 10⁻³ )
n = 1.54125 / 4.4396226 × 10⁻²⁶
n = 3.4716 × 10²⁵ m⁻³
Therefore, the density of mobile electrons in the material is 3.4716 × 10²⁵ m⁻³
Answer:
78.498N
Explanation:
The Net force provided by the spinnaker can be obtained from Newton's second law of motion as follows;

where m is the mass, v is the final velocity, u is the initial velocity and t is the time interval for which the force acted.
Given;
m =980lb
v = 12mi/h
u =8mi/hr
t = 10s.
It is important to convert all quantities to their SI units where necessary, so we do that as follows;
1lb = 0.45kg,
hence 980lb = 980 x 0.45kg = 441kg.
1mile = 1609.34m
1hour = 3600s,
therefore;


Substituting all values into equation (1), we obtain the following;
