many answers to this question so chose whatever you link:
- urbanisation -> more people, humanity keeps on living, more job opportunities etc
- source of income for farmers
- source for food (farming)
- source for trees (eg, to create wood (houses), or to use logs for fire)
Answer:
162.8 K
Explanation:
initial current = io
final current, i = io/8
Let the potential difference is V.
coefficient of resistivity, α = 43 x 10^-3 /K
Let the resistance is R and the final resistance is Ro.
The resistance varies with temperature
R = Ro ( 1 + α ΔT)
V/i = V/io (1 + α ΔT )
8 = 1 + 43 x 10^-3 x ΔT
7 = 43 x 10^-3 x ΔT
ΔT = 162.8 K
Thus, the rise in temperature is 162.8 K.
Answer: 
Explanation:
let this sign be ∅ (titha in degrees)
let coefficient of friction of 0.200 be u
and i be current i= 1.41A
mass m=1.14g/cm m=0.0114g/m
To find the magnetic field from the north will be:
tan ∅= u
∅=
∅=11.3°
The direction:
i L*B cos(∅)= umg
divide both by iLcos(∅) to find B
B= 
where m=
B= 
B= 
Constant acceleration is when the velocity changes the same amount in every equal time period. For example : 9.8 m/s^2
Instantaneous acceleration is the rate at which velocity changes at a specific instant in time. For example: at one point it might be 8m/s^2 and at another point 13m/s^2
Answer
a) charge of the sodium ion is,
q = n e
q = 2.68 x 10¹⁶ x 1.6 x 10⁻¹⁹
q = 4.288 x 10⁻³ C
charge of the chlorine ion is,
q' = n e
q' = 3.92 x 10¹⁶ x 1.6 x 10⁻¹⁹
q' = 6.272 x 10⁻³ C
the current
b) positive ion moves toward negative electrode hence direction of will be in the direction toward negative electrode.
