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3 years ago

Which change indicates that the universe is expanding?

Physics

2 answers:

Aleonysh [2.5K]3 years ago

5 0

Red shift of distant galaxies

rodikova [14]3 years ago

3 0

Red shift of distant galaxies

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As a laudably skeptical physics student, you want to test Coulomb's law. For this purpose, you set up a measurement in which a p

Oksana_A [137]

Answer:

a.Attractive

$2.31531\times 10^{-16}\ N$

Explanation:

When it comes to charges, the charges which are alike repel each other and the charges which are different will attract each other.

Here, there is a proton and electron which are different particles hence, they will attract each other.

$q_1=q_2$ = Charge of electron and proton = $1.6\times 10^{-19}\ C$

r = Distance between them = 997 nm

k = Coulomb constant = $8.99\times 10^{9}\ Nm^2/C^2$

Force is given by

$F=\dfrac{kq_1q_2}{r^2}\\\Rightarrow F=\dfrac{8.99\times 10^9\times 1.6\times 10^{-19}\times 1.6\times 10^{-19}}{(997\times 10^{-9})^2}\\\Rightarrow F=2.31531\times 10^{-16}\ N$

The force of attraction between the particles will be $2.31531\times 10^{-16}\ N$

8 0

3 years ago

Use the impulse-momentum theorem to find how long a stone falling straight down takes to increase its speed from 3.7 m/s to 9.90

11111nata11111 [884]

<h2>Time taken is 0.632 seconds</h2>

Explanation:

Impulse momentum theorem is change in momentum is impulse.

Change in momentum = Impulse

Final momentum - Initial momentum = Impulse

Mass x Final velocity - Mass x Initial Velocity = Force x Time

Mass x Final velocity - Mass x Initial Velocity =Mass x Acceleration x Time

Final velocity - Initial Velocity = Acceleration x Time

Final velocity = 9.9 m/s

Initial Velocity = 3.7 m/s

Acceleration = 9.81 m/s²

Substituting

9.9 - 3.7 = 9.81 x Time

Time = 0.632 seconds

Time taken is 0.632 seconds

8 0

2 years ago

Why do astronauts need to wear pressurized suits in space?

SashulF [63]

The correct answer is C , because the space is vacuum and his body can explode and for this reason, the astronaut need a special costum to be protected. It's the same on the moon, because there is no atmosphere

6 0

3 years ago

Think about a typical school day. In the space provided below, describe how each of the different forms of energy we have learne

Nezavi [6.7K]

Answer:

During a typical school day all forms of eneergy is being utilised and also transfer of energy takes place from one form to another.

Explanation:

Chemical energy- A bunsen burner burning a beaker filled with water.

Heat energy- The water in the beaker absorbing the heat from the burner.

Electrical energy- Running Fans and lights in a classroom by switches.

Solar energy- Solar energy harnessed by solar panels to run the fans and lights by converting it into electrical energy.

Potential energy- A ball being held by a student at a certain height possesses energy due to gravity.

Kinetic energy- The same ball being left by the boy from a certain height produces kinetic energy

3 0

2 years ago

Read 2 more answers

A punted football hits the ground with a force of 50 N . According to Newton’s 3rd law of motion what also happens at the same e

Nadya [2.5K]

As per Newton's III law every action has equal and opposite reaction

So here we can say that

every body which apply force on other body must have a reaction force of same magnitude in opposite direction

So here if ball hits the ground by 50 N force then the ball must have a reaction force on itself with same magnitude and opposite direction

the magnitude of the force will be 50 N

and its direction is opposite to the force that ball apply on the floor

4 0

3 years ago