Muscular strength is BEST described by

An astronaut is being tested in a centrifuge. The centrifuge has a radius of 11.0 m and, in starting, rotates according to θ = 0

Mazyrski [523]

Answer:

a) 1.248 rad/s

b) 13.728 m/s

c) 0.52 rad/s^2

d) 17.132m/s^2

Explanation:

You have that the angles described by a astronaut is given by:

$\theta=0.260t^2$

(a) To find the angular velocity of the astronaut you use the derivative og the angle respect to time:

$\omega=\frac{d\theta}{dt}=\frac{d}{dt}[0.260t^2]=0.52t$

Then, you evaluate for t=2.40 s:

$\omega=0.52(2.40)=1.248\frac{rad}{s}$

(b) The linear velocity is calculated by using the following formula:

$v=\omega r$

r: radius if the trajectory of the astronaut = 11.0m

You replace r and w and obtain:

$v=(1.248\frac{rad}{s})(11.0m)=13.728\frac{m}{s}$

(c) The tangential acceleration is:

$a_T=\alpha r\\\\\alpha=\frac{\omega^2}{2\theta}=\frac{(1.248rad/s)^2}{2(0.260(2.40s)^2)}=0.52\frac{rad}{s^2}$

(d) The radial acceleration is:

$a_r=\frac{v^2}{r}=\frac{(13.728m/s)^2}{11.0m}=17.132\frac{m}{s^2}$

4 0

4 years ago

The cornea of the eye has a radius of curvature of approximately 0.40 cm , and the aqueous humor behind it has an index of refra

My name is Ann [436]

Answer:

0.64814 cm

Explanation:

$n_1$ = Refractive index of air = 1

$n_2$ = Refractive index of aqueous humor = 1.35

u = Object distance = $\infty$

v = Image distance = 25 mm

R = Radius of curvature of the cornea

Lens equation

$\dfrac{n_2-n_1}{R}=\dfrac{n_1}{u}+\dfrac{n_2}{v}\\\Rightarrow \dfrac{1.35-1}{R}=\dfrac{1}{\infty}+\dfrac{1.35}{2.5}\\\Rightarrow \dfrac{1.35-1}{R}=\dfrac{1.35}{2.5}\\\Rightarrow \dfrac{0.35}{R}=\dfrac{1.35}{2.5}\\\Rightarrow R=\dfrac{0.35\times 2.5}{1.35}\\\Rightarrow R=0.64814\ cm$

Radius of curvature of the cornea is 0.64814 cm

5 0

4 years ago

Which conversion is the function of a photovoltaic cell? A) sunlight to mechanical energy B) electricity to heat C) sunlight to

irakobra [83]

Answer:

C. Sunlight to electricity

Explanation:

Photo voltaic cells covert sunlight to the electricity. It absorbs the light from the sun and use that sunlight to create electric current. The number of photo voltaic cells are connected together in a solar panel to generate enough electricity to power up a home.

3 0

3 years ago

An object has a coefficient of kinetic friction of 0.2 and a normal force of 30N. Find the force of kinetic friction.

shutvik [7]

Answer:

Force of kinetic friction, Fk = 6N

Explanation:

Given the following data;

Coefficient of kinetic friction, μ = 0.2

Normal force, Fn=30N

To find the Force of kinetic friction;

Mathematically, the force of kinetic friction is given by the formula;

Fk = μFn

Where;

Fk represents the force of kinetic friction.

μ represents the coefficient of friction.

Fn represents the normal force.

Substituting into the equation, we have;

Fk = 0.2*30

Fk = 6N

Therefore, the force of kinetic friction is 6N.

6 0

4 years ago

A 6.30 kg piece of solid copper metal at an initial temperature T is placed with 2.00 kg of ice that is initially at -16.0 ∘C. T

Viktor [21]

Answer:

179 degree

Explanation:

Solid copper will lose heat to warm up and melt ice . Since all the ice has not melted so final temperature of mixture will be zero.

heat gained by ice to reach temperature of zero degree

= mass of ice x specific heat of ice x rise of temp

= 2 x 2093 x 16 = 66976 J

Heat gained to melt 1.1. kg of ice

mass x latent heat of ice

1.1 x 334000

= 367400

total heat

= 367400 + 66976

=434376

Heat lost by copper

= 6.3 x 385 x T

where 385 is specific heat of copper and T is initial temperature

heat lost = heat gained

6.3 x 385 T = 434376

T = 434376 / (6.3 x 385)

= 179 degree .

3 0

3 years ago