Answer:
47947.52 J.
Explanation:
From the question,
Amount of heat given of (Q) = mc(t₁–t₂).................... Equation 1
Where m = mass of water, c = specific heat capacity of water, t₁ = initial temperature, t₂ = final temperature.
Given, m = 640 g = 640 g, c = 4.816 J/g°C, t₁ = 76 °C, t₂ = 28 °c.
Substitute these values into equation 1 above
Q = 640×4.816(48)
Q = 147947.52 J.
Hence the amount of heat given off is 47947.52 J.
Answer:

Explanation:
From work energy theorem
Work done by all forces = Change in kinetic energy
Lets take
m= mass of object
h=height from the ground surface
initial velocity of object = 0 m/s
The final velocity of object is v
Work done by gravitational force = m g . h
The final kinetic energy = 1/2 m v²
So
Work done by all forces = Change in kinetic energy
m g h = 1/2 m v² - 0
v² = 2 g h

Answer:
On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At Earth's surface the acceleration of gravity is about 9.8 metres (32 feet) per second per second.
Answer:
coal, oil and natural gas.
Explanation:
Fossil fuel is a general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the earth's crust over hundreds of millions of years.
Answer:
a mixture
since it had the power to separate as the question says