A train moves at constant velocity of 90km/h. How far will it go in 0.25h.

For a point charge, how does the potential vary with distance from the point charge, r?

mr_godi [17]

For a point charge, how does the potential vary with distance from the point charge, r?

a constant

b. r.

c. 1/r.

d. $1/r^2$ .

e. $r^2$ .

Answer:

The correct option is C

Explanation:

Generally for a point charge the electric potential is mathematically represented as

$V = \frac{k Q }{r }$

Here we can deduce that the electric potential varies inversely with the distance i.e

$V \ \alpha \ \frac{1}{r}$

So

3 0

3 years ago

Defined the term electromagnetic induction and explain how a generator uses electromagnetic induction

tatuchka [14]

Is the production of electricity by magnetic field.

There are two types of generator which is D.C generator . And A.C generator

A.C gen consist of rectangular coil,brushes and permanent magnet

According to the external force mechanical energy used to rotate coil, due to magnetic flux produced by permanent magnet create induced current, this is to according to flemmings right hand rule of electromagnetic induction the rotating coil will produce current

I hope that will help.

8 0

3 years ago

How does Lenz's Law illustrate the concept that "you can't get

Crazy boy [7]

Answer:

When there is a change in magnetic flux linkage through a loop of wire, an electromotive force is induced in the loop, according to the Faraday-Newmann-Lenz Law:

$\epsilon=-\frac{N\Delta \Phi}{\Delta t}$

where

N is the number of turns in the loop

$\Delta \Phi$ is the change in magnetic flux through the loop

$\Delta t$ is the time elapsed

The negative sign in the formula represents Lenz's Law, and tells us about the direction of the electromotive force.

In fact, the negative sign means that the direction of the induced emf is such that to oppose to the change in the magnetic flux that originated the induced emf.

This is a consequence of the law of conservation of energy: no energy can be created out of nowhere. In fact, when the emf is induced in the loop, electrical energy appears in the circuit; however, this electric energy cannot come out of nowhere. Instead, it is just "created" from the transformation of some other form of energy (for instance, the mechanical energy that is used to move the loop in the magnetic field, and changing its magnetic flux).

The negative sign in Lenz's Law tells exactly this: the direction of the induced emf is such that it opposes the initial change in magnetic flux that generated the induced emf, so that overall the total energy is conserved.

5 0

2 years ago

Scientists often use models to study the movement of continents. Why might scientists use a model to show this movement? A. Extr

egoroff_w [7]

Answer:

Paleontologists have argued for a long time that the demise of the dinosaurs was caused by climatic alterations associated with slow changes in the positions of continents and seas resulting from plate tectonics. Off and on throughout the Cretaceous (the last period of the Mesozoic era, during which dinosaurs flourished), large shallow seas covered extensive areas of the continents. Data from diverse sources, including geochemical evidence preserved in seafloor sediments, indicate that the Late Cretaceous climate was milder than today's. The days were not too hot, nor the nights too cold. The summers were not too warm, nor the winters too frigid. The shallow seas on the continents probably buffered the temperature of the nearby air, keeping it relatively constant.

3 0

2 years ago

Read 2 more answers

A tennis player hits a ball 2.0 m above the ground. The ball leaves his racquet with a speed of 20 m/s at an angle 5.0 ∘ above t

goldfiish [28.3K]

Answer:

Explanation:

initial height, yo = 2 m

initial velocity, u = 20 m/s

angle of projection,θ = 5 degree

distance of net = 7 m

height of net = 1 m