The specific heat of water is 4.2 J/g • °C. How much heat is required to raise the temperature of 100 g of water by 5°C? *
1 answer:
Answer:
2100 J
Explanation:
The heat required to increase the temperature of a substance is given by
where
m is the mass of the substance
C is its specific heat capacity
is its change in temperature
For the water in this problem, we have:
m = 100 g is its mass
C = 4.2 J/g • °C is the specific heat capacity
is the increase in temperature
So, the amount of heat needed is:
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Explanation:
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where:
is the initial potential energy, at the bottom
is the initial kinetic energy, at the bottom
is the final potential energy, at the top
is the final kinetic energy, at the top
We can rewrite the equation as:
where:
m is the mass of the hopper
is the acceleration of gravity
is the initial height
u is the launch speed of the hopper
is the maximum altitude reached by the hopper
v = 0 is the final speed (which is zero when the hopper reaches the maximum height)
Solving the equation for u, we find the launch speed of the hopper:
Learn more about kinetic energy and potential energy:
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