A Rocket took 5 minutes to travel the 185 km. How fast did the Rocket travel in kilometers per minute (km/min)?

An aluminum cylinder with a radius of 2.7 cm and a height of 67 cm is used as one leg of a workbench. The workbench pushes down

soldier1979 [14.2K]

Answer:

$1.9\times 10^{-4}$

$1.2\times 10^{-4}\ m$

Explanation:

r = Radius = 2.7 cm

F = Force = $3.2\times 10^4\ N$

A = Area = $\pi r^2$

$\sigma$ = Stress = $\frac{F}{A}$

E = Young's modulus = $7\times 10^{10}\ Pa$

$\epsilon$ = Strain

$L_0$ = Original length = 67 cm

$\Delta L$ = Change in length

Young's modulus is given by

$E=\frac{\sigma}{\epsilon}\\\Rightarrow \epsilon=\frac{\sigma}{E}\\\Rightarrow \epsilon=\frac{\frac{3.2\times 10^4}{\pi 0.027^2}}{7\times 10^{10}}\\\Rightarrow \epsilon=0.0001996=1.9\times 10^{-4}$

Strain is $1.9\times 10^{-4}$

Strain is given by

$\epsilon=\frac{\Delta L}{L_0}\\\Rightarrow \Delta L=\epsilon\times L_0\\\Rightarrow \Delta L=1.9\times 10^{-4}\times 0.67\\\Rightarrow \Delta L=0.0001273\\\Rightarrow \Delta L=1.2\times 10^{-4}\ m$

The cylinder height decreases by $1.2\times 10^{-4}\ m$

3 0

3 years ago

Please help! the mass of an object is measured on a pan balance with a precision of 0.005 g and the recorded value of 128.01 g.

inysia [295]

Yes, these two objects have different masses.

<h3>How can we calculate that this statement is right ?</h3>

To calculate the precision of mass we are using the formula,

Precision(P) = $\frac{m_1}{m_1+\triangle m}$

Or, $\triangle$ m= $\frac{m_1}{P}$ -m₁

For the first case we are given,

m₁= The recorded value of mass

= 128.01 g

P= Precision of the mass

=0.005g

So, according to the formula, $\triangle$ m will be,

$\triangle$ m= $\frac{128.01}{0.005}$ -128.01

Or, $\triangle$ m=25,473.99 g

Or, $\triangle$ m=25.47 Kg

For the first case $\triangle$ m is 25.47 Kg..

For the second case we are given,

m₁= The recorded value of mass

= 0.13 Kg

P= Precision of the mass

=0.005 Kg

So, according to the formula, $\triangle$ m will be,

$\triangle$ m= $\frac{0.13}{0.005}$ -0.13

Or, $\triangle$ m= 25.87 kg

For the second case $\triangle$ m is 25.87 Kg.

For the two cases $\triangle$ m has different values, 25.47 Kg≠25.87 Kg.

Therefore we can conclude that, these two objects have different masses.

Learn more about Mass:

brainly.com/question/3187640

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7 0

2 years ago

A 6,600 kg train car moving at +2.0 m/s bumps into and locks together with one of mass 5,400 kg moving at -3.0 m/s.

Katarina [22]

Option B would be right one
according to momentum conservation
6600*2 = 13200kgm/s
5400*3 = 16200kgm/s
16200-13200 = 3000
now 6600-5400 = 1200 kg
thus 3000/1200 = 2.5 v

5 0

3 years ago

Swimmers at the beach are tanning on towels. Which method of heat transfer is responsible for their tan? *

Free_Kalibri [48]

Answer:

ratiation

Explanation:

3 0

3 years ago

Read 2 more answers

Which of the following is true regarding the properties of light?

Ivanshal [37]

Light having a dual nature and acting like both a wave and a particle is the correct statement in this scenario.

<h3>What is Light?</h3>

This refers to the electromagnetic radiation found in the electromagnetic spectrum that is perceived by the human eye and has a dual nature. It doesn't require a medium for its propagation unlike sound.

The dual nature of light is as a result of it behaving like a photon which is why it travels in straight lines.

It also behave like a wave because it undergoes processes such as reflection, refraction etc which are common to waves.

Read more about Light here brainly.com/question/1363382

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6 0

1 year ago