Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T
Resistivity, 
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :
r = 0.00199 m
or
The magnetic field on a current carrying wire is given by :
I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
Answer:
The correct answer is a
Explanation:
At projectile launch speeds are
X axis vₓ = v₀ = cte
Y axis 
= v_{oy} –gt
The moment is defined as
p = mv
For the x axis
pₓ = mvₓ = m v₀ₓ
As the speed is constant the moment is constant
For the y axis
p_{y} = m v_{y} = m (v_{oy} –gt) = m v_{oy} - m (gt)
Speed changes over time, so the moment also changes over time
Let's examine the answer
i True
ii False. The moment changes with time
The correct answer is a
A group of students toured a limestone cave in northwest Georgia.
Which of these best explains how the limestone caves in Georgia were formed?
A. Plant roots split the rock.
B. Acidic water dissolved the rock.
C. Animals burrowed into the rock.
D. Ice formed and broke up the rock.
Answer:
A car accelerating to the right
Explanation:
The free-body diagram shows all the forces acting on an object. The length of each arrow is proportional to the magnitude of the force represented by that arrow.
In this free-body diagram, we see that there are 4 forces acting on the object, in 4 different directions. We also see that the two vertical forces are equal so they are balanced, while the force to the rigth is larger than the force to the left: this means that there is a net force to the right, so the object is accelerating to the right.
Therefore, the correct answer is:
A car accelerating to the right
Answer:
Statement 1 can be matched with option f (Van der waal forces)
Statement 2 can be matched with option b (Liquid crystal)
statement 3 can be matched with option e (Thermal expansion)
Statement 4 can be matched with option g (Viscosity)
Statement 5 can be matched with option b (Fractional distillation)
Statement 6 can be matched with option a (Diffusion)
Statement 7 can be matched with option d (Miscible)
Explanation:
- Van der waal forces are weak inter-molecular bonds found between covalent molecules e.g molecules of graphite, noble gases etc
- Liquid crystals are substances that behave like liquids and its molecules orientate itself like a crystal (solid). They can be referred to as LCs.
- Thermal expansion is a phenomenon where by matter changes in shape, volume and area due to a change in temperature.
- Viscosity is a term used to describe a fluid's resistance to flow. It is also used to describe the internal friction that a moving liquid experiences. Oil is more viscose than liquid water
- Fractional distillation is a separation technique used in separating two or more miscible liquids of close boiling points. For example petrol and diesel oil can be separated using fractional distillation. An industrial application of this technique is Fractional distillation of crude oil where crude oil is separated into its components
- Diffusion is the movement of dissolved particles, gases, liquid from a region of higher concentration to a region of lower concentration until there is a equal balance. This can occur when you spray a perfume in one end of a room. You will get to smell the perfume at the other end after some time. Diffusion is fastest in gas as compared to liquids and solids.
- Miscible is a word used to describe liquids forming a homogeneous mixture when dissolved in each other. Miscibility is factor to be considered when separating mixture.
