How high up is a 3kg object that has 300 joules of energy

An electron is accelerqated in the uniform field betwen two parallel charged oplates. The separation of the plates is 1.20 cm

marysya [2.9K]

Answer:

The speed of electron is $8.7\times10^{6}\ m/s$

Explanation:

Given that,

Separation of the plate = 1.20 cm

Suppose the field is $E=1.80\times10^{4}\ N/C$ .

If the electron is accelerated from rest near the negative plate and passes through a tiny hole in the positive plate.

What the speed does it leave the hole?

We need to calculate the acceleration

Using formula of electric force

$F = qE$

$ma=qE$

$a=\dfrac{qE}{m}$

We need to calculate the speed of electron

Using equation of motion

$v^2=u^2+2as$

$v^2=2as$

Put the value of acceleration in the formula

$v^2=2\times\dfrac{qE}{m}\times s$

Put the value into the formula

$v^2=2\times\dfrac{1.6\times10^{-19}\times1.80\times10^{4}\times1.20\times10^{-2}}{9.11\times10^{-31}}$

$v=\sqrt{2\times\dfrac{1.6\times10^{-19}\times1.80\times10^{4}\times1.20\times10^{-2}}{9.11\times10^{-31}}}$

$v=8.7\times10^{6}\ m/s$

Hence, The speed of electron is $8.7\times10^{6}\ m/s$

7 0

3 years ago

The internal energy of a system changes because the system gains 160 J of heat and performs 309 J of work. In returning to its i

o-na [289]

Answer:

w=255

Explanation:

The change in internal energy is given by the first law:

ΔE = Q - w

where ΔE is the change in internal energy of the system

q is the heat added to the system

w is the work done *by* the system on the surroundings

So, for the first phase of this process:

ΔE = Q - w

Q=160J

w=309J

ΔE = 160J - 309J = -149J

To bring the system back to its initial state after this, the internal energy must change by +149J (the system myst gain back the 149 J of energy it lost). We are told that the system loses 106 J of heat in returning to its initial state, so the work involved is given by:

ΔE = Q - w

+149J = -106J - w

255J = -w

w = -255J

5 0

3 years ago

“A famous person to themselves, they don't get up in the morning and think, I'm famous. I'm not famous to me. Famous is a percep

Fynjy0 [20]

I would say B because different people see famous people in different ways. like a famous person would just see them self as a person whereas a non-famous person would see them as amazing and superior to others.

8 0

4 years ago

Read 2 more answers

#1. On a school bus traveling 22 m/s , students walks to the back of the bus at a rate of 1m/s . What is the speed of the studen

zhuklara [117]

#1 is C#2 is C aswell

5 0

3 years ago

A car starts from rest and after 10 seconds is traveling at 20 m/s. Assuming that it continues to accelerate at the same rate it

Alenkinab [10]

Assuming that it continues to accelerate at the same rate it will take another 10 seconds to reach 40 m/s.

Answer:

Explanation:

Since the first question states that there is a change in the velocity from rest to 20 m/s in 10 seconds time interval. So the acceleration experienced by the car during this 10 seconds should be determined first as follows:

Acceleration = (final velocity-initial velocity)/Time

Acceleration = (20-0)/10 = 2 m/s².

So this means the car is traveling with an acceleration of 2 m/s².

As it is stated that the car continues to move with same acceleration, then in the second case, the acceleration is fixed as 2 m/s², initial velocity as 20 m/s and final velocity as 40 m/s. So the time taken for the car to reach this velocity with the constant acceleration value will be as follows:

Time = Change in velocity/Acceleration

Time = (40-20)/2 = 20/2=10 s

So again in another 10 seconds by the car to reach 40 m/s from 20 m/s. Similarly the car will take a total of 20 seconds to reach from rest to 40 m/s value for velocity.

5 0

3 years ago