Blood cell : ____________ :: bacteria : ________________

One model for a certain planet has a core of radius R and mass M surrounded by an outer shell of inner radius R, outer radius 2R

Tanzania [10]

(a) $24.6 m/s^2$

At a distance r=R from the centre of the planet, there is no effect due to the outer shell: so, the gravitational field strength at r=R is only determined by the gravity produced by the core of the planet.

So, the strength of the gravitational field is given by

$g= \frac{GM}{R^2}$

where

G is the gravitational constant

M = 6.24 × 10^24 kg is the mass of the core of the planet

R = 4.11 × 10^6 m is the radius of the core

Substituting into the equation, we find

$g= \frac{(6.67\cdot 10^{-11})(6.24\cdot 10^{24} kg)}{(4.11\cdot 10^6 m)^2}=24.6 m/s^2$

(b) $13.7 m/s^2$

at distance r=3R from the centre, the particle feels the effect of gravity due to both the core of the planet and the outer shell between R and 2R.

So, we have to consider the total mass that exerts the gravitational attraction at r=3R, which is the sum of the mass of the core (M) and the mass of the shell (4M):

M' = M + 4M = 5M

Therefore, the gravitational acceleration at r=3R will be

$g'= \frac{G(5M)}{(3R)^2}=\frac{5}{9}\frac{GM}{R^2} = \frac{5}{9}g$

And susbstituting

g = 24.6 m/s^2

found in the previous part, we find

$g' = \frac{5}{9} (24.6 m/s^2)=13.7 m/s^2$

6 0

3 years ago

A student performed an experiment with a metal sphere. The student shot the sphere from a slingshot and measured its maximum hei

cestrela7 [59]

The correct answer is Launch angle

Explanation:

The Independent Variable can be easily identified because this is the factor or variable the researcher modifies. In this case, this term applies to the angle because as part of the experiment the student changes the angle multiple times to test how the maximum height changes. Moreover, the maximum height would be the dependent variable as it is the main factor and it changes or depends on other variables including the angle. Thus, it can be concluded the independent variable is the launch angle or the angle from which the ball is launched.

5 0

3 years ago

True or false<br> Hydrogen fuel cells generate electricity by combining hydrogen with oxygen.

adoni [48]

Answer:

The answer is: True.

Explanation:

If free electrons or other substances could travel through the electrolyte, they would disrupt the chemical reaction. Whether they combine at anode or cathode, together hydrogen and oxygen form water, which drains from the cell. As long as a fuel cell is supplied with hydrogen and oxygen, it will generate electricity.

(Credit: Google)

7 0

3 years ago

Which of the following characteristics is a quality of a socially developing economy?

tensa zangetsu [6.8K]

Answer:

C

Explanation:

Got it right

7 0

3 years ago

Read 2 more answers

Calculate the mass of 1.35 moles of sodium chloride (NaCl).

Harlamova29_29 [7]

Answer:d

Explanation:

4 0

3 years ago

Blood cell : ____________ :: bacteria : _________________

Blood cell : :: bacteria : _____