Answer:
B. I, III and IV
Explanation:
The strength of the magnetic field generated by a solenoid is given by the following formula:
B = μ₀NI/L
where,
B = Magnetic Field
μ₀ = Permeability of Free Space
N = No. of Coils
I = Current Magnitude
L = Length of Coil
Strength is also directly proportional to size of the core.
So, to increase the magnetic field strength we can:
1- The number of Loops
2- Increase the amount of Current (for same length)
3- Decrease the length (for same number of loops)
4- Increase Size of Core
So, the correct answer is:
<u>B. I, III and IV</u>
Answer:
No
Explanation:
Let's assume the gas pressure is constant. Then we can use Charle's law, which states that the volume of the gas is proportional to the absolute temperature (in Kelvin):
This can be rewritten as
where we have
is the initial temperature of the gas
is the final temperature of the gas
Re-arranging the previous equation, we find
so, the volume of the gas decreases by a factor 0.87.
Answer:
W = 85.73 m
Explanation:
given,
surveyor walks = 118 m
makes an angle of = 36.0° with the tree
to find the width of the river
W = 85.73 m
hence, the width of the river is equal to W = 85.73 m