To determine the distance of the light that has traveled given the time it takes to travel that distance, we need a relation that would relate time with distance. In any case, it would be the speed of the motion or specifically the speed of light that is travelling which is given as 3x10^8 meters per second. So, we simply multiply the time to the speed. Before doing so, we need to remember that the units should be homogeneous. We do as follows:
distance = 3x10^8 m/s ( 8.3 min ) ( 60 s / 1 min ) = 1.494x10^11 m
Since we are asked for the distance to be in kilometers, we convert
distance = 1.494x10^11 m ( 1 km / 1000 m) = 149400000 km
Answer:
Explanation:
Given
Cross-sectional area of wire
Extension of wire
Extension in a wire is given by
where,
for same force, length and material
Divide (i) and (ii)
TLDR: It will reach a maximum when the angle between the area vector and the magnetic field vector are perpendicular to one another.
This is an example that requires you to investigate the properties that occur in electric generators; for example, hydroelectric dams produce electricity by forcing a coil to rotate in the presence of a magnetic field, generating a current.
To solve this, we need to understand the principles of electromotive forces and Lenz’ Law; changing the magnetic field conditions around anything with this potential causes an induced current in the wire that resists this change. This principle is known as Lenz’ Law, and can be described using equations that are specific to certain situations. For this, we need the two that are useful here:
e = -N•dI/dt; dI = ABcos(theta)
where “e” describes the electromotive force, “N” describes the number of loops in the coil, “dI” describes the change in magnetic flux, “dt” describes the change in time, “A” describes the area vector of the coil (this points perpendicular to the loops, intersecting it in open space), “B” describes the magnetic field vector, and theta describes the angle between the area and mag vectors.
Because the number of loops remains constant and the speed of the coils rotation isn’t up for us to decide, the only thing that can increase or decrease the emf is the change in magnetic flux, represented by ABcos(theta). The magnetic field and the size of the loop are also constant, so all we can control is the angle between the two. To generate the largest emf, we need cos(theta) to be as large as possible. To do this, we can search a graph of cos(theta) for the highest point. This occurs when theta equals 90 degrees, or a right angle. Therefore, the electromotive potential will reach a maximum when the angle between the area vector and the magnetic field vector are perpendicular to one another.
Hope this helps!
Answer:
The blade of sharpener is made up of iron. Iron is a magnetic material because of this pencil sharpener gets attracted by the poles of a magnet although the body is made up of plastic.
Answer:
D. Battery
During the oxidation-reduction(redox) reaction, there is always flow of electrons from one point to another. The electrons are then converted to power through the battery which converts chemical energy to electrical energy. If there is zero flow of electrons then there will also be zero power.