Longitudional waves travel through a series of ________ and __________

A 400g mass object at rest is acted on by a 200 N net force for 12 seconds. What is it’s final velocity?

Kisachek [45]

Explanation:

do we can say that the first step is finding the acceleration of the object. We do so by saying F = ma

so a = F/m

a = 500 m/s^2

we now have the time, acceleration and initial velocity.

so we can find the final velocity by using one of newtons equations which is: vf = vi + at

so:

vf = 0 + 500 × 12

vf = 6000

note that our initial velocity was zero since the object was initially at rest.

if you still have any doubt dont hesitate to ask for further help.

3 0

2 years ago

The total resistance of a 15-ohm, an 65-ohm and a 35-ohm resistor connected in parallel

yanalaym [24]

Answer:

I think its 9.0397 Ohms

Explanation:

take the reciprocal of all the resistances: 1/15, 1/65, 1/35

then add them: = 151/1365

then reciprocal the answer: =1365/151

And chuck it on a calculator: =9.04 Ohms

I think this is right but I'm not entirely sure. Tell me if I'm right by the way!

3 0

3 years ago

The molecules in metal are usually more tightly packed than the molecules in water. Most metals will sink in water. Pick your co

satela [25.4K]

Answer:

Metal is more dense than water.

Explanation:

As we know, the molecules of the metal are tightly closed as compared to that of water and the density of a material is defined as the mass of the material per unit volume.

In a certain volume of metal, there are more numbers of molecules than that of water in the same amount of volume, therefore the density of metal is greater than that of water.

Also, according to Archimedes' principle, if there is an object in a fluid, then the buoyant force on that object is equal to the weight of the fluid that it displaces.

When the density of the object is larger than that of the fluid then it overcomes that buoyant force and sinks.

Thus, an object sinks in a fluid if its density is larger than that of the fluid and floats otherwise.

Since, the metal sink in water, it means Metal is more dense than water.

5 0

4 years ago

Two boxers are fighting. Boxer 1 throws his 5 kg fist at boxer 2 with a speed of 9 m/s.

Sladkaya [172]

Answer:

0.001 s

Explanation:

The force applied on an object is equal to the rate of change of momentum of the object:

$F=\frac{\Delta p}{\Delta t}$

where

F is the force applied

$\Delta p$ is the change in momentum

$\Delta t$ is the time interval

The change in momentum can be written as

$\Delta p=m(v-u)$

where

m is the mass

v is the final velocity

u is the initial velocity

So the original equation can be written as

$F=\frac{m(v-u)}{\Delta t}$

In this problem:

m = 5 kg is the mass of the fist

u = 9 m/s is the initial velocity

v = 0 is the final velocity

F = -45,000 N is the force applied (negative because its direction is opposite to the motion)

Therefore, we can re-arrange the equation to solve for the time:

$\Delta t=\frac{m(v-u)}{F}=\frac{(5)(0-9)}{-45,000}=0.001 s$

4 0

3 years ago

A camera phone called the iPhone X has an image sensor size of 5 mm and a focal length of 4 mm. How long of a selfie-stick must

azamat

Answer:

length of selfie-stick is 1.62 m

Explanation:

Given data

image size h1 = 5 mm = 5 × $10^{-3}$ m

focal length = 4 mm = 4 × $10^{-3}$ m

distance h2 = 2.032 m

to find out

How long of a selfie-stick

solution

here we find first magnification

that is M = h1 /h2

M = 5 × $10^{-3}$ / 2.032

M = 2.46 × $10^{-3}$

and we know M = p/q

so p = Mq = 2.46 × $10^{-3}$ q

so we apply lens formula

1/f = 1/p - 1/q

1/ 4 × $10^{-3}$ = 1 / 2.46 × $10^{-3}$ q - 1/q

q = 1.622 m

so length of selfie-stick is 1.62 m

4 0

3 years ago

Longitudional waves travel through a series of ________ and ___________.

Longitudional waves travel through a series of and ___.