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3 years ago

A 77.0 kg firefighter climbs a flight of stairs 8.0 m high. how much work is required? 0 incorrect: your answer is incorrect. j

1 answer:

5 0

<span>6160 joules

to lift 1 newton 1 metre requires 1 joule
there are 10 newtons in one kilo

so 77(kg) x 8 (metres) x 10 (newtons/kilo) = 6160 joules</span>

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What does this indicate about the claim?

Anton [14]

claim

[klām]

VERB

state or assert that something is the case, typically without providing evidence or proof.

"he claimed that he came from a wealthy, educated family" · [more]

synonyms:

assert · declare · profess · maintain · state · hold · affirm · avow · aver · [more]

NOUN

an assertion of the truth of something, typically one that is disputed or in doubt.

"he was dogged by the claim that he had CIA links" · [more]

synonyms:

assertion · declaration · profession · affirmation · avowal · averment · protestation · representation · contention · submission · case · allegation · pretense · asseveration

a demand or request for something considered one's due.

"the court had denied their claims to asylum"

7 0

3 years ago

Read 2 more answers

1) Determine the magnitude of energy for each of the blanks on the diagram. Give the correct values for 1A, 1B, and 1C.

morpeh [17]

Answer:

Explanation: y’all taking the same test as me hahahahah I got the answers but I can’t attach the picture here so hit me up on snap daniela_0789

4 0

3 years ago

What is the impulse of a 3 kg object that starts from rest and moves to 20 m/s?

IrinaK [193]

Answer:

The impulse on the object is 60Ns.

Explanation:

Impulse is defined as the product of the force applied on an object and the time at which it acts. It is also the change in the momentum of a body.

F = m a

F = m( $\frac{v_{2} - v_{1} }{t}$ )

⇒ Ft = m( $v_{2}$ - $v_{1}$ )

where: F is the dorce on the object, t is the time at which it acts, m is the mass of the object, $v_{1}$ is its initialvelocity and $v_{2}$ is the final velocity of the object.

Therefore,

impulse = Ft = m( $v_{2}$ - $v_{1}$ )

From the question, m = 3kg, $v_{1}$ = 0m/s and $v_{2}$ = 20m/s.

So that,

Impulse = 3 (20 - 0)

= 3(20)

= 60Ns

The impulse on the object is 60Ns.

8 0

2 years ago

Why does a dropped object only fall 5 meters down after 1 second of freefall, yet achieve a speed of 10m/s?

andrew11 [14]

A dropped object only fall 5 meters down after 1 second of freefall, yet achieve a speed of 10m/s due to acceleration due to gravity.

s = vt - 1 / 2 at²

s = Displacement

v = Final velocity

t = Time

a = Acceleration

s = 5 m

t = 1 s

a = 10 m / s²

5 = ( v * 1 ) - ( 1 / 2 * 10 * 1 * 1 )

5 = v - 5

v = 10 m / s

The equation used to solve the given problem is an equation of motion. In a free fall motion, usually air resistance is not considered for easier calculation. If air resistance is considered acceleration cannot be constant throughout the entire motion.

Therefore, a dropped object only fall 5 meters down after 1 second of freefall, yet achieve a speed of 10m/s due to acceleration due to gravity.

To know more about equation of motion

brainly.com/question/5955789

#SPJ1

4 0

7 months ago

Will mark as brainliest if correct!!!!!!!

lutik1710 [3]

C. A could be ruby (speed of light = 170,000 km/s); B could be diamond (speed of light = 120,000 km/s).

Explanation:

Refraction is a phenomenon that occurs when a light rays crosses the boundary between two different mediums.

When this occurs, the light wave changes speed and also direction, according to Snell's law:

$n_1 sin \theta_1 = n_2 sin \theta_2$ (1)

where

$n_1$ is the index of refraction of the first medium

$n_2$ is the index of refraction of the second medium

$\theta_1$ is the angle of incidence (the angle between the incident ray and the normal to the boundary)

$\theta_2$ is the angle of refraction (the angle between the refracted ray and the normal to the boundary)

The index of refraction is the ratio between the speed of light in a vacuum (c) and the speed of light in the medium (v):

$n=\frac{c}{v}$

Using this definition, we can rewrite eq.(1) as

$\frac{\sin \theta_2}{\sin \theta_1} = \frac{v_2}{v_1}$

Where $v_2$ is the speed of light in the 2nd medium and $v_1$ the speed of light in the 1st medium.

Now let's analyze the situation represented in the figure: we see that as the light ray enters the 2nd medium, it bends towards the normal, this means that the angle of refraction is smaller than the angle of incidence:

$\theta_2 < \theta_1$

This means that

$\frac{\sin \theta_2}{\sin \theta_1}$

And therefore,

$\frac{v_2}{v_1}$

So, the speed of light in the second medium is smaller than the speed of light in the first medium: this occurs only in option C), which is therefore the correct choice.

Learn more about refraction:

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6 0

3 years ago