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marshall27 [118]

3 years ago

10

Oh no! The Hulk just fell off the Empire State Building! Calculate how long it took him to fall straight down from the top of th

e Empire State Building, which is 380 m high.

1 answer:

nekit [7.7K]3 years ago

3 0

Answer:it takes approximately 148.8 seconds to achieve. The average person in a free-fall will hit the ground going at 9.66 m/s from the top of the Empire State Building.

Explanation:

You might be interested in

If you were to walk at a constant speed 20m/s for 30 seconds, how far would you walk?

lana [24]

Answer:

600m

Explanation:

30×20 at a constant speed is 600m.

6 0

4 years ago

How can energy be traced as it is converted<br> through different transformations?

Mumz [18]

Answer:

Energy transformations are processes that convert energy from one type (e.g., kinetic, gravitational potential, chemical energy) into another. Any type of energy use must involve some sort of energy transformation.

8 0

4 years ago

6. What is the change in temperature of a metal rod that is 55.0 cm long, decreases length by 0.20 cm, and that has a coefficien

MrMuchimi

Explanation:

We have,

Length of a metal rod is 55 cm or 0.55 m

Change in length is 0.2 cm or 0.002 m

It is required to find the change in temperature of a metal rod. The coefficient of linear expansion is given by :

$\alpha =\dfrac{\Delta L}{L_0\Delta T}$

$\Delta T$ is the change in temperature

$\Delta T =\dfrac{\Delta L}{L_0\alpha }\\\\\Delta T =\dfrac{0.002}{0.55\times 12\times 10^{-6}}\\\\\Delta T= 303.03^{\circ} C$

So, the change in temperature is 303.03 degrees Celsius.

4 0

3 years ago

A bicycle is traveling with a speed of 12 m/s. The cyclist hits the brakes reducing the speed to 4 m/s in a time of 4.8 seconds.

Annette [7]

So, the acceleration of the bicycle is approximately <u>-1.67 m/s²</u> or it can be said to be decelerating approximately <u>1.67 m/s²</u>.

<h3>Introduction</h3>

Hi ! Here I will help material about linear motion changes regularly, which is where you will hear a lot of the term acceleration. Acceleration occurs when an object's speed increases in a certain time interval. Acceleration can be negative which is called deceleration. The relationship between acceleration with velocity and time is manifested in the equation:

$\boxed{\sf{\bold{a = \frac{v_2 - v_1}{t}}}}$

With the following conditions :

a = acceleration (m/s²)
$\sf{v_2}$ = object's final velocity (m/s)
$\sf{v_1}$ = object's initial velocity (m/s)
t = interval of the time (s)

<h3>Problem Solving </h3>

We know that :

$\sf{v_2}$ = object's final velocity = 4 m/s
$\sf{v_1}$ = object's initial velocity = 12 m/s
t = interval of the time = 4.8 s

What was asked :

a = acceleration = ... m/s²

Step by step :

$\sf{a = \frac{v_2 - v_1}{t}}$

$\sf{a = \frac{4 - 12}{4.8}}$

$\sf{a = \frac{-8}{4.8}}$

$\boxed{\sf{a \approx -1.67 \: m/s^2}}$

So, the acceleration of the bicycle is about -1.67 m/s² or it can be said to be decelerating around 1.67 m/s².

8 0

3 years ago

The filament of a certain lamp has a resistance that increases linearly with temperature. When a constant voltage is switched on

sashaice [31]

To solve this problem we can apply the concept related to thermal expansion, including the analogy with resistance and final intensity.

The mathematical expression that describes the expansion of a material by a thermal process is given by

$R = R_0\alpha \Delta T$

Where

$R_0$ = Initial resistance

$\alpha =$ Thermal expansion coefficient

$\Delta T =$ Change in the temperature

If we want to directly obtain the final value of the resistance of the object, you would simply add the initial resistance to this equation - because at this moment we have the result of how much resistance changed, but not of its final resistance - So,

$R_f = R_0 + L_0\alpha \Delta T$

$R_f = R_0(1 + \alpha \Delta T)$

Re-arrange to find the change at the temperature,

$\Delta T=\frac{1}{\alpha}\frac{R_f}{R_0}-1}$

Since the resistance is inversely proportional to the current and considering that the voltage is constant then

$R \propto \frac{1}{I}$

Then,

$\Delta T=\frac{1}{\alpha}\frac{I_0}{I_f}-1}$

$\Delta T = \frac{1}{4.5*10^{-3}}(\frac{I_0}{I_0/8}-1)$

$\Delta T = \frac{1}{4.5*10^{-3}}(8-1)$

$\Delta T = 1555.5k$

<em>(It is possible that there is a typing error and the value is not 4.5 but 4.3, so the closest approximate result would be 1627K and mark this as the correct answer)</em>

6 0

3 years ago