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3 years ago

If you answer this I will give you brainliest whoever answers first!!!

Physics

1 answer:

rusak2 [61]3 years ago

4 0

Explanation:

this graph show the decrease in velocity with time

at time t=0 velocity is 40 m/sec

at time t=12sec velocity is decreases from 40 to 10 m/s

so the acceleration of the object at time=12 sec is

a=v/t

a=Δv/t

Δv=v1-v2=40-10=30 m/s

a=30/12=2.5 m/s^2

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The ball will oscillate along the z axis between z=dz=d and z=−dz=−d in simple harmonic motion. What will be the angular frequen

Eddi Din [679]

Answer:

$\omega = \sqrt{\dfrac{kq_0Q}{ma^3} }$

Explanation:

Additional information:

<em>The ball has charge </em> $-q_0$ <em>, and the ring has positive charge </em> $+Q$ <em> distributed uniformly along its circumference. </em>

The electric field at distance $z$ along the z-axis due to the charged ring is

$E_z= \dfrac{kQz}{(z^2+a^2)^{3/2}}.$

Therefore, the force on the ball with charge $-q_0$ is

$F=-q_oE_z$

$F=- \dfrac{kq_0Qz}{(z^2+a^2)^{3/2}}$

and according to Newton's second law

$F=ma=m\dfrac{d^2z}{dz^2}$

substituting $F$ we get:

$- \dfrac{kq_0Qz}{(z^2+a^2)^{3/2}}=m\dfrac{d^2z}{dz^2}$

rearranging we get:

$m\dfrac{d^2z}{dz^2}+ \dfrac{kq_0Qz}{(z^2+a^2)^{3/2}}=0$

Now we use the approximation that

$z^2+a^2\approx a^2$ <em>(we use this approximation instead of the original </em> $d^2+a^2\approx a^2$ <em> since </em> $z$ <em>, our assumption still holds )</em>

and get

$m\dfrac{d^2z}{dz^2}+ \dfrac{kq_0Qz}{(a^2)^{3/2}}=0$

$m\dfrac{d^2z}{dz^2}+ \dfrac{kq_0Qz}{a^{3}}=0$

Now the last equation looks like a Simple Harmonic Equation

$m\dfrac{d^2z}{dz^2}+kz=0$

where

$\omega=\sqrt{ \dfrac{k}{m} }$

is the frequency of oscillation. Applying this to our equation we get:

$m\dfrac{d^2z}{dz^2}+ \dfrac{kq_0Q}{a^{3}}z=0\\\\m=m\\\\k= \dfrac{kq_0Q}{a^{3}}$

$\boxed{\omega = \sqrt{\dfrac{kq_0Q}{ma^3} }}$

5 0

4 years ago

Calculate the frequency if the number of revolutions is 300 and the paired poles are 50.

Andrei [34K]

Answer: A

Explanation: We know that f=p*n

f=50*300=15000 Hz = 15kHz.

Have a great day! <3

3 0

2 years ago

A ball at the top of a hill is an example of ______ and a ball rolling down the hill is an example of ______.

larisa [96]

Potential energy , Kinetic energy

<h3 /><h3>What is kinetic energy and potential energy?</h3>

Kinetic energy is a form of energy that posses by an object due to its motion. If work, which transfers energy, is done on an object by applying a net force, the object speeds up and thereby gains kinetic energy.

Potential energy is the energy held by an object due to its position relative to other objects, stresses within itself, its electric charge, or other factors.

According to given condition,

At first,

When a ball is at the top of a hill , it posses a potential energy because the ball is at some height from the surface where the energy held by ball is due to its position.

That is why, a ball at the top of a hill is an example of Potential energy.

Secondly,

When a ball is rolling down the hill , it posses kinetic energy because the ball have some energy that posses by an object due to its motion.

That is why, a ball rolling down the hill is an example of Kinetic energy.

Learn more about Potential energy and Kinetic energy here:

brainly.com/question/11749818

#SPJ1

6 0

2 years ago

Help with velocity math pls help asap

pychu [463]

2 is the answer have a nice day <3

5 0

3 years ago

Some people say it is rare to get HIV from a blood transfusion in the United States. True or false? Why?

iragen [17]

Answer:

False

Explanation:

Because there is a 90% chance of contracting HIV from a blood transfusion

8 0

3 years ago