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3 years ago

When you lift a book of the ground to your desk, what kind of work do you do, negative or positive?

1 answer:

8 0

It would be kinetic energy. Let's say the book is weighs 10 Newtons you need to use a force of 10 Newtons to lift the book. In other words it's positive. As you move the book you're giving it energy. Namely potential energy which will turn to kinetic energy if you let it go. So you're changing it's position and energy.

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Two pendulum bobs have equal masses and lengths (8.100 m). bob a is initially held horizontally while bob b hangs vertically at

Karo-lina-s [1.5K]

Since both hv same mass and elsstic collision, so their velocity will exchange. Bob A will stop and bob B will move with speed of A just before the collision.

Speed will be = squreroot ( 2*g*L)

L is length of pendulum

5 0

3 years ago

Read 2 more answers

Which term is applied to an object through which light passes?

Elena L [17]

Answer:

Explanation:

transparent_objects that allows light to pass through and can you see through them

5 0

3 years ago

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Which circuit is a series circuit ?? plz help

gregori [183]

In a series circuit, all of the components are connected in the same 'loop' and the current only has one direction/path it can flow through.

In the first three options, the current has multiple paths it can go through. So these three circuits are parallel and not series.

In the last option, the current only has one path where it can flow through, so that circuit is in series.

So Circuit <u>D </u>is a series circuit.

----------------------------------------

Answer

Circuit D

7 0

3 years ago

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Find the pressure if a force of 2N is applied to an area of 0.00004m^2

BigorU [14]

Answer:

5 x 10^4 N/m^2

Explanation:

Pressure, force and area are related witg the following equation;

Pressure = Force /Area

From the question, we obtained the following information;

Force = 2N

Area = 0.00004m^2

Pressure =?

Pressure = Force /Area

Pressure = 2/0.00004

Pressure = 5 x 10^4N/m^2

3 0

3 years ago

At what speed, as a fraction of c , is a particle's total energy twice its rest energy

WINSTONCH [101]

The rest energy of a particle is
$E_0=m_0 c^2$
where $m_0$ is the rest mass of the particle and c is the speed of light.

The total energy of a relativistic particle is
$E=mc^2 = \frac{m_0 c^2}{ \sqrt{1- \frac{v^2}{c^2} } }$
where v is the speed of the particle.

We want the total energy of the particle to be twice its rest energy, so that
$E=2E_0$
which means:
$\frac{m_0c^2}{ \sqrt{1- \frac{v^2}{c^2} } }=2m_0 c^2$
$\frac{1}{ \sqrt{1- \frac{v^2}{c^2} } }=2$
From which we find the ratio between the speed of the particle v and the speed of light c:
$\frac{v}{c}= \sqrt{1- (\frac{1}{2})^2 } =0.87$
So, the particle should travel at 0.87c in order to have its total energy equal to twice its rest energy.

3 0

3 years ago