An object changes velocity from 100m/s

A sports car accelerates from rest to 27.8 m/s in 4.80 s. What magnitude force does the 66.0 kg driver experience during the acc

kkurt [141]

Acceleration= change in velocity/time=27.8-0/4.8=5.792 ms⁻²
Force= Mass*acceleration=66*5.792=382.25 N

6 0

4 years ago

An electric dipole having dipole moment of magnitude p is placed in a uniform electric field having magnitude E. What is the mag

Daniel [21]

Answer:

Explanation:

The formula for the potential energy of a dipole placed in an electric field is given by

U = - pE Cos θ

where, θ is the angle between dipole moment and the electric field vector.

For θ = 0°,

initial potential energy, Ui = - pE

For θ = 180°,

final potential energy, Uf = - pE Cos 180 = pE

Change in potential energy

ΔU = Uf - Ui

ΔU = pE - (-pE)

ΔU = 2pE

5 0

4 years ago

Newton's Law of Gravitation says that the magnitude F of the force exerted by a body of mass m on a body of mass M is F = GmM r2

Nookie1986 [14]

<h2>Answers:</h2>

According to Newton's Law of Gravitation, the Gravity Force is:

$F=\frac{GMm}{{r}^{2}}$ (1)

This expression can also be written as:

$F=GMm{r}^{-2}$ (2)

If we derive this force $F$ respect to the distance $r$ between the two masses:

$\frac{dF}{dr}dFdr=\frac{d}{dr}(GMm{r}^{-2})dr$ (3)

Taking into account $GMm$ are constants:

$\frac{dF}{dr}dFdr=-2GMm{r}^{-3}$ (4)

Or

$\frac{dF}{dr}dFdr=-2\frac{GMm}{{r}^{3}}$ (5)

<h2> (b) dF/dr represents the rate of change of the force with respect to the distance between the bodies. </h2><h2 />

In other words, this means how much does the Gravity Force changes with the distance between the two bodies.

More precisely this change is inversely proportional to the distance elevated to the cubic exponent.

As the distance increases, the Force decreases.

<h2>(c) The minus sign indicates that the bodies are being forced in the negative direction. </h2>

This is because Gravity is an attractive force, as well as, a central conservative force.

This means it does not depend on time, and both bodies are mutually attracted to each other.

In the first answer we already found the decrease rate of the Gravity force respect to the distance, being its unit $N/km$ :

$\frac{dF}{dr}dFdr=-2\frac{GMm}{{r}^{3}}$ (5)

We have a force that decreases with a rate 1 $\frac{dF_{1}}{dr}dFdr=4N/km$ when $r=20000km$ :

$4N/km=-2\frac{GMm}{{(20000km)}^{3}}$ (6)

Isolating $-2GMm$ :

$-2GMm=(4N/km)({(20000km)}^{3})$ (7)

In addition, we have another force that decreases with a rate 2 $\frac{dF_{2}}{dr}dFdr=X$ when $r=10000km$ :

$XN/km=-2\frac{GMm}{{(10000km)}^{3}}$ (8)

Isolating $-2GMm$ :

$-2GMm=X({(10000km)}^{3})$ (9)

Making (7)=(9):

$(4N/km)({(20000km)}^{3})=X({(10000km)}^{3}$ (10)

Then isolating $X$ :

$X=\frac{4N/km)({(20000km)}^{3}}{{(10000km)}^{3}}$

Solving and taking into account the units, we finally have:

$X=-32N/km$ >>>>This is how fast this force changes when $r=10000 km$

7 0

4 years ago

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An airplane starts from rest and accelerates at a constant 3.00 m/s2

katrin2010 [14]

Answer:600 m

Explanation:

6 0

3 years ago

How does an iron nail become a magnet when it is placed in a strong magnetic field

lord [1]

Metals, especially iron, have this form of electron cloud around it. When it's placed in a magnetic field these electrons line up

5 0

3 years ago

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