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3 years ago

Two steel blocks rest on a frictionless, horizontal surface. Block X has a mass of

Physics

1 answer:

stepan [7]3 years ago

3 0

Before you jump into this, you have to stand back, look at it, and decide what's going to happen.

You're pulling on some things that rest on a frictionless surface, so they have to start moving. In fact, they're going to accelerate.

Now, I want you to consider for just a second: What would happen if
the two blocks were glued together ? Then, you'd be pulling on a single
18-kg block, with 36N of force, and it would accelerate to the right at
[ A = F/M ] = 36/18 = 2 m/s² .

The actual situation is no different. The string between them has no weight,
and it's tight, and there are no other forces on the blocks, so the whole combination ... both blocks ... is still going to accelerate to the right at 2 m/s² .

OK. Now, let's look at the individual blocks:

The one in the back ... the 12 kg. It's accelerating at 2 m/s² to the right,
so the force on it must be [ F = M A ] = 12 x 2 = 24 N to the right. Where
does that force come from ? It's the tension in the string between them.

The one in the front ... the 6-kg.
It has 36 N pulling it to the right, and 24 N of string tension pulling it to the left.
The net force on this block is (26 - 24) = 12N to the right.
Its acceleration is [ A = F/M ] = 12/6 = 2m/s² to the right.

Well, whaddaya know ! Both blocks accelerate at the same rate, in the
same direction, just as if they were glued together, and the string between
them remains tight, with 24N of tension in it.

With this description, you can handle the FBD on your own, I'm sure.

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A gas exerts less pressure when it has a

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The molecules are continually colliding with each other and with the walls of the container. When a molecule collides with the wall, they exert small force on the wall The pressure exerted by the gas is due to the sum of all these collision forces.The more particles that hit the walls, the higher the pressure.

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3 years ago

In Anchorage, collisions of a vehicle with a moose are so common that they are referred to with the abbreviationMVC. Suppose a 1

lara31 [8.8K]

Answer:

Part a)

$f = \frac{8}{9}$

Part b)

$f = \frac{120}{169}$

Part c)

So from above discussion we have the result that energy loss will be more if the collision occurs with animal with more mass

Explanation:

Part a)

Let say the collision between Moose and the car is elastic collision

So here we can use momentum conservation

$m_1v_{1i} = m_1v_{1f} + m_2v_{2f}$

$1000 v_o = 1000 v_{1f} + 500 v_{2f}$

also by elastic collision condition we know that

$v_{2f} - v_{1f} = v_o$

now we have

$2v_o = 2v_{1f} + v_o + v_{1f}$

now we have

$v_{1f} = \frac{v_o}{3}$

Now loss in kinetic energy of the car is given as

$\Delta K = \frac{1}{2}m(v_o^2 - v_{1f}^2)$

$\Delta K = \frac{1}{2}m(v_o^2 - \frac{v_o^2}{9})$

so fractional loss in energy is given as

$f = \frac{\Delta K}{K}$

$f = \frac{\frac{4}{9}mv_o^2}{\frac{1}{2}mv_o^2}$

$f = \frac{8}{9}$

Part b)

Let say the collision between Camel and the car is elastic collision

So here we can use momentum conservation

$m_1v_{1i} = m_1v_{1f} + m_2v_{2f}$

$1000 v_o = 1000 v_{1f} + 300 v_{2f}$

also by elastic collision condition we know that

$v_{2f} - v_{1f} = v_o$

now we have

$10v_o = 10v_{1f} + 3(v_o + v_{1f})$

now we have

$v_{1f} = \frac{7v_o}{13}$

Now loss in kinetic energy of the car is given as

$\Delta K = \frac{1}{2}m(v_o^2 - v_{1f}^2)$

$\Delta K = \frac{1}{2}m(v_o^2 - \frac{49v_o^2}{169})$

so fractional loss in energy is given as

$f = \frac{\Delta K}{K}$

$f = \frac{\frac{60}{169}mv_o^2}{\frac{1}{2}mv_o^2}$

$f = \frac{120}{169}$

Part c)

So from above discussion we have the result that energy loss will be more if the collision occurs with animal with more mass

8 0

2 years ago

A sound wave in the air has a frequency of 256 hertz and is traveling at a speed of 331 meters/second. What is its wavelength?

nikdorinn [45]

2.39 is the answer cuh

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3 years ago

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In order to make an electromagnet, you need a

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All you need to do is wrap some insulated copper wire around an iron core. If you attach a battery to the wire, an electric current will begin to flow and the iron core will become magnetized. When the battery is disconnected, the iron core will lose its magnetism.

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2 years ago

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Do you think there are any forces acting on the ball when it is rolling around the inside of the roll of tape? Why or why not?

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Yes because it is sticky

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1 year ago