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Novosadov [1.4K]

4 years ago

8

A bag of ice cubes absorbs 149,000 J of heat, which causes its temperature to increase by 5.23 degrees celsius. what is the mass

of the ice in the bag?
Ice=c=2000J/(kg*c) (unit=kg)

1 answer:

Dima020 [189]4 years ago

6 0

Answer:

14.3kg

Explanation:

Given parameters:

Quantity of heat = 149000J

Change in temperature = 5.23°C

specific heat of the ice = 2000J/kg°C

Unknown:

Mass of the ice in the bag = ?

Solution:

The heat capacity of a substance is given as:

H = m c Ф

H is the heat capacity

m is the mass

c is the specific heat

Ф is the temperature change;

since m is the unknown, we make it the subject of the expression;

m = H/ mФ

m = $\frac{149000}{2000 x 5.23}$ = 14.3kg

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Substitute 2.27 m for s (=h₁), 0.301 s for t and 9.8 m/s² for a (=g).

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If the acorn starts from rest and reaches a speed of 6.067 m/s at the top of the scale, it would have fallen a distance h₂ to achieve this speed.

Use the equation of motion,

$v^2=u^2+2as$

Substitute 6.067 m/s for v, 0 m/s for u, 9.8 m/s² for a (=g) and h₂ for s.

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