The current in a resistor is 3.0 A, and its power is 60 W. What is the voltage?

What is the kinetic energy of an object that has a mass of 50.0kg and a velocity of 18 m/s?

Rom4ik [11]

<h2>Answer </h2>

The kinetic energy is 8100 J.

<u>Explanation</u>

Mass is 50.0kg and velocity is 18 m/s, the kinetic energy is:

As we know the formula of kinetic energy which is K.E = ½ ( mv ^ 2 ),

mass = m = 50.0kg

velocity = v = 18 m / s,

by putting values in the formula,

K.E = ½ ( mv ^ 2 ),

K.E = ½ ( 50kg ) . ( 18 m / s ) ^ 2

K.E = ½ ( 50kg ) . ( 324 ),

=> K.E = 1/2 ( 16200 ),

=> K.E = 16200 / 2,

=> K.E = 8100J.

Hence, the kinetic energy ( K.E ) is 8100 joule ( J ).

7 0

3 years ago

True or False. Can Metalloids conduct electricity under certain conditions?

EleoNora [17]

Answer:

Conduction: Some metalloids, such as silicon and germanium, can act as electrical conductors under the right conditions, thus they are called semi-conductors. Luster: Silicon for example appears lustrous, but is not malleable or ductile (it is brittle - a characteristic of some nonmetals).

Explanation:

4 0

2 years ago

You have a radioactive sample with a half-life of 1 hour. At t = 1 hour, a Geiger counter measures its radiation at 40 counts/mi

Mama L [17]

Answer:

Explanation:

Given that, .

The half-life of a radioactive element is

t½ = 1 hr.

At the first hour, the radioactive element has 40 counts/minute

After 4 hours it has 5 counts/minute

So,

We want to filled the table.

0 hours, I.e at the start

40 counts/mins × 2 = 80 counts / mis

First half-life (first hour) is

40 counts/mins

Second half-life (second hour)

40 counts/mins × ½ = 20 counts/mins

Third half-life (third hour)

40 counts/mins × ¼ = 10 counts / mins

Fourth half life (fourth hour)

40 counts/mins × ⅛ = 5 counts / mins

So, the table is

Time........................Geiger Counter Rate

0 hours.................... 80 counts / minutes

1 hour........................ 40 counts / minutes

2 hours..................... 20 counts / minutes

3 hours..................... 10counts / minutes

4 hours...................... 5 counts / minute

6 0

3 years ago

In the Bohr model of the hydrogen atom, an electron moves in a circular path around a proton. The speed of the electron is appro

blondinia [14]

In order to answer these questions, we need to know the charges on
the electron and proton, and then we need to know the electron's mass.
I'm beginning to get the creepy feeling that, in return for the generous
5 points, you also want me to go and look these up so I can use them
in calculations ... go and collect my own straw to make the bricks with,
as it were.

Ok, Rameses:

Elementary charge . . . . . 1.6 x 10⁻¹⁹ coulomb
negative on the electron
plussitive on the proton

Electron rest-mass . . . . . 9.11 x 10⁻³¹ kg

a). The force between two charges is

F = (9 x 10⁹) Q₁ Q₂ / R²

= (9 x 10⁹ m/farad) (-1.6 x 10⁻¹⁹C) (1.6 x 10⁻¹⁹C) / (5.35 x 10⁻¹¹m)²

      = ( -2.304 x 10⁻²⁸) / (5.35 x 10⁻¹¹)²

=    8.05 x 10⁻⁸ Newton .

b). Centripetal acceleration =

   v² / r .

A = (2.03 x 10⁶)² / (5.35 x 10⁻¹¹)

   =    7.7 x 10²² m/s² .

That's an enormous acceleration ... about 7.85 x 10²¹ G's !
More than enough to cause the poor electron to lose its lunch.

It would be so easy to check this work of mine ...
First I calculated the force, then I calculated the centripetal acceleration.
I didn't use either answer to find the other one, and I didn't use " F = MA "
either.

I could just take the ' F ' that I found, and the 'A' that I found, and the
electron mass that I looked up, and mash the numbers together to see
whether F = M A .

I'm going to leave that step for you.   Good luck !

4 0

3 years ago

Water is completely filling black metallic vessel having cubic form and thin walls. The mass of water is 1 kg and initial temper

Brilliant_brown [7]

Answer:

Check the attached image

Explanation:

To solve the problem for time you will have to use the formula for time, t = d/s which means time equals distance divided by speed.

Kindly check the attached image below for the step by step explanation to the question.

5 0

3 years ago