this is a link to a web sight with a diagram to help you
https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwjw4v7knNDgAhVyUN8KHWgWD-wQjRx6BAgBEAU&url=%2Furl%3Fsa%3Di%26source%3Dimages%26cd%3D%26ved%3D%26url%3Dhttps%253A%252F%252Ffuturism.com%252Fwhere-do-all-the-elements-come-from%26psig%3DAOvVaw19_FOCuWs_nMsyY1YT0Da-%26ust%3D1550955269844922&psig=AOvVaw19_FOCuWs_nMsyY1YT0Da-&ust=1550955269844922
Answer:
m₁ = 0.37 kg
Explanation:
According to Law of conservation of energy:
Heat Lost by Aluminum = Heat Gained by Water
m₁C₁ΔT₁ = m₂C₂ΔT₂
where,
m₁ = mass of piece of aluminum = ?
C₁ = specific heat capacity of aluminum = 900 J/kg.°C
ΔT₁ = Change in temperature of aluminum = 250°C - 22°C = 228°C
m₂ = mass of water = 9 kg
C₂ = specific heat capacity of water = 4200 J/kg.°C
ΔT₁ = Change in temperature of aluminum = 22°C - 20°C = 2°C
Therefore,
m₁(900 J/kg.°C)(228 °C) = (9 kg)(4200 J/kg.°C)(2°C)
m₁ = (75600 J)/(205200 J/kg)
<u>m₁ = 0.37 kg</u>
Answer:
c) At a distance greater than r
Explanation:
If G= Gravitational constant
M= Mass of earth
r= distance from earth center
then orbital speed is ;
v = 
==> v²=GM/r
If speed of first satellite = V₁
==> V₁² = GM/r
==> r = GM/V₁²
If speed of second satellite say V₂ is less than V₁ then square of V₂ will be less than square of V₁ , and hence GM will be divided by less number in case of second satellite, and hence will give greater value of r as compared to first satellite.
So our answer is c
The insect's velocity is 0.2 meter/second along east.
<h3>What is velocity?</h3>
The rate at which a body's displacement changes in relation to time is known as its velocity. Velocity is a vector quantity with both magnitude and direction. SI unit of velocity is meter/second.
Given parameters:
An insect crawls 4 m east along a hiking path.
Time taken by it: t = 20 seconds.
We have to fine: the insect's velocity, v =?
So, the magnitude of velocity: v= 4/20 meter/second = 0.2 meter/second.
And the direction velocity is along east.
Hence, the insect's velocity is 0.2 meter/second along east.
Learn more about velocity here:
brainly.com/question/18084516
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