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3 years ago

A car is moving at constant velocity towards a brick wall.

Physics

1 answer:

Ulleksa [173]3 years ago

8 0

Answer:

Upon sensing a collision the seat belts lock in place. When the car crashes, there is no unbalanced force acting on the person, so they continue forward (Newton's First Law). The person moves against the seat belt, exerting a force on it. The seat belt then exerts a force back on the person (Newton's Third Law).

Explanation:

You might be interested in

Non example of a Mass Number

Zielflug [23.3K]

Are there any options or is it not a multiple choice question.

4 0

4 years ago

What mass of steam at 100°C must be mixed with 490 g of ice at its melting point, in a thermally insulated container, to produce

sukhopar [10]

Answer:

the mass of steam at 100°C must be mixed is 150 g

Explanation:

given information:

ice's mass, $m_{i}$ = 490 g = 0.49 kg

steam temperature, T = 100°C

liquid water temperature, T = 89.0°C

specific heat of water, $c_{w}$ = 4186 J/kg.K = 4.186 kJ/kg.K

latent heat of fusion, $L_{f}$ = 333 kJ/kg

latent heat of vaporization, $L_{v}$ = 2256 kJ/kg

first, we calculate the heat of melted ice to water

Q₁ = $m_{i} L_{f}$

where

Q = heat

$m_{i}$ = mass of the ice

$L_{f}$ = latent heat of fusion

thus,

Q₁ = $m_{i} L_{f}$

= 0.49 x 333

= 163.17 kJ

then, the heat needed to increase the temperature of water to 89.0°C

Q₂ = $m_{i}$ $c_{w}$ (89 - 0), the temperature of ice is 0°C

$c_{w}$ = specific heat of water

so,

Q₂ = $m_{i}$ $c_{w}$ (89 - 0)

= 0.49 x 4.186 x 89

= 182.55 kJ

so, the heat absorbed by the ice is

Q = Q₁ + Q₂

= 163.17 + 182.55

= 345.72 kJ

the temperature of the steam is 100°C, so the mass of the steam is

Q = $m_{s}$ $L_{v}$ + $m_{s}$ $c_{w}$ (100 - 89)

Q = $m_{s}$ ( $L_{v}$ + $c_{w}$ (11))

$m_{s}$ = Q/ [ $L_{v}$ + $c_{w}$ (11)]

= 345.72/ [2256 + (4.186 x 11)]

= 0.15 kg

= 150 g

5 0

3 years ago

What units should be used when measuring the mass of a ladybug?

Aleks [24]

You could use grams hope this helps

3 0

3 years ago

Why are the parts of an atom that electrons occupy called electron clouds?

Anna [14]

Because it's literally impossible to tell exactly where something that size is
located at any particular time.

And that's NOT because it's so small that we can't see it. It's because any
material object behaves as if it's made of waves, and the smaller the object is,
the more the size of its waves get to be like the same size as the object.
When you get down to things the size of subatomic particles, it doesn't make
sense any more to try and talk about where the particle actually "is", and we only
talk about the waves that define it, and how the waves all combine to become a
cloud of <em><u>probability</u></em> of where the particle is.

I know it sounds weird. But that's the way it is. Sorry.

8 0

3 years ago

Help with these please someone

Mice21 [21]

Answer:

Five: B

Ten: A

Explanation:

Five

An alpha decay looks like this.

$A^x_y====> B^{x-4}_{y - 2}+alpha^4_2$

So whatever is produced must have a mass of 4 less than 234 and a number on the periodic table of 2 less than 92. In other words, B has a mass of 230 and a number on the periodic table of 90.

The answer should be Thorium which is B.

Ten

There is actually not enough information to do 10. You get it by making an assumption and seeing if it works.

In general a beta decay can (the most common one ) look like this.

$A^x_y====> B^{x}_{y-1}+Beta^0_{-1}$

Is there anything that looks like that?

The weight stays the same (234) and the atomic number of the mother element (on the left) is 1 lower than the given chemical on the right.

$Th^{234}_{90}====> Pa^{234}_{91}+Beta^0_{-1}$

The answer is Thorium A

Beta decays are very tricky. Be very careful how you handle them. One of three items can be what is decayed. I have assumed it was an electron, but there are two other possibilities. I won't confuse you by adding them. Just be aware that they exist.

3 0

3 years ago