In the Bohr model of the atom, an electron in an orbit has a fixed ___

How much kinetic energy does a 50 kg object have if its moving at a velocity of 2 m/s?

bulgar [2K]

Answer:

C) 100 joules

Explanation:

The kinetic energy of an object is given by:

$K=\frac{1}{2}mv^2$

where m is the mass of the object and v its speed.

In this problem, we have an object of mass m = 50 kg and v = 2 m/s, so by using the formula we can find its kinetic energy:

$K=\frac{1}{2}(50 kg)(2 m/s)^2=100 J$

3 0

3 years ago

How much work must be done to bring three electrons from a great distance apart to 5.0×10^−10 m from one another (at the corners

Inessa05 [86]

Answer:

1.38 x 10^-18 J

Explanation:

q = - 1.6 x 10^-19 C

d = 5 x 10^-10 m

the potential energy of the system gives the value of work done

The formula for the potential energy is given by

$U =\frac{Kq_{1}q_{2}}{d}$

So, the total potential energy of teh system is

$U =\frac{Kq_{1}q_{2}}{d}+\frac{Kq_{2}q_{3}}{d}+\frac{Kq_{1}q_{3}}{d}$

As all the charges are same and the distance between the two charges is same so the total potential energy becomes

$U =3\times \frac{Kq^{2}}{d}$

K = 9 x 10^9 Nm^2/C^2

By substituting the values

$U =3\times \frac{9\times 10^{9}\times \ 1.6 \times 1.6 \times 10^{-38}}{5\times 10^{-10}}$

U = 1.38 x 10^-18 J

6 0

3 years ago

Objects 1 and 2

sattari [20]

Answer:

12 units

Explanation:

Original F = C q1q2/r^2 now change the parameters

New F = C 1/3 q1 2 q2 / (2r)^2

= 2/12 C q1q2/r^2 <=======the new force is 1/6 of original

1/6 * 72 = 12 units

3 0

2 years ago

1.- An elevator is being lowered at a constant speed by a steel cable attached to an electric motor. Which statement is correct?

Nady [450]

Answer:

the correct one is C

Explanation:

For this exercise we must use the work definition

W = F. s

Where the bold characters indicate vectors and the point is the scalar producer

W = F s cos θ

Where θ is the angles between force and displacement.

Let us support this in our case. The cable creates an upward tension and with the elevator going down the angle between them is 180º so the work of the cable on the elevator is negative.

The evade has a downward force, its weight so the force goes down and the displacement goes down, as both are in the same direction the work is positive

When examining the statements the correct one is C

4 0

3 years ago

Sirius, the brightest star in the sky, is 2.6 parsecs (8.6 light-years) from Earth, giving it a parallax of 0.379 arcseconds. An

Vikentia [17]

Answer: Sirius, the brightest star in the sky, is 2.6 parsecs (8.6 light-years) from Earth, giving it a parallax of 0.379 arcseconds. Another bright star, Regulus, has a parallax of 0.042 arcseconds. Then, the distance in parsecs will be,23.46.

Explanation: To find the answer, we have to know more about the relation between the distance in parsecs and the parallax.

<h3>What is the relation between the distance in parsecs and the parallax?</h3>

Let's consider a star in the sky, is d parsec distance from the earth, and which has some parallax of P amount.
Then, the equation connecting parallax and the distance in parsec can be written as,

$d=\frac{1}{P}$