Skip to main content
Ch. 19 - Heat and the First Law of Thermodynamics
Giancoli Douglas - Physics for Scientists and Engineers 5th edition
Giancoli Douglas5th editionPhysics for Scientists and EngineersISBN: 9780137488179Non è quello che usi tu?Cambia libro di testo
Tutti i libri di testoGiancoli Douglas 5th editionCh. 19 - Heat and the First Law of ThermodynamicsProblema 99a
Capitolo 19, Problema 99a

Calculate what will happen when 1000 J of heat is added to 100 grams of ice at -20°C.

Guida verificata passo dopo passo
1
Step 1: Determine the heat required to raise the temperature of the ice from -20°C to 0°C. Use the formula Q=mcΔT, where m is the mass of the ice (100 g = 0.1 kg), c is the specific heat capacity of ice (2,100 J/kg·°C), and ΔT is the temperature change (20°C).
Step 2: Check if the remaining heat is sufficient to melt the ice. The heat required to melt the ice is calculated using the formula Q=mL, where L is the latent heat of fusion for ice (334,000 J/kg).
Step 3: If there is still heat remaining after melting the ice, calculate the heat required to raise the temperature of the resulting water from 0°C to a higher temperature. Use the formula Q=mcΔT, where c is the specific heat capacity of water (4,186 J/kg·°C).
Step 4: Compare the total heat added (1,000 J) to the sum of the heat required for each step. If the heat is insufficient to complete a step, stop at that point and determine the final state of the system (e.g., partially melted ice or water at a certain temperature).
Step 5: Summarize the final state of the system, specifying whether the ice is fully melted, partially melted, or if the water has reached a certain temperature.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
3m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Specific Heat Capacity

Specific heat capacity is the amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius. For ice, this value is approximately 2.09 J/g°C. Understanding this concept is crucial for calculating how much the temperature of ice will increase when heat is added.
Video consigliato:
Percorso guidato
06:50
Specific Heat & Temperature Changes

Phase Changes

Phase changes refer to the transitions between solid, liquid, and gas states of matter. When heat is added to ice, it may first increase the temperature until it reaches 0°C, and then the heat will be used to convert the ice into water at the melting point. This process requires additional energy known as the latent heat of fusion.
Video consigliato:
Percorso guidato
10:40
Latent Heat & Phase Changes

Energy Conservation

The principle of energy conservation states that energy cannot be created or destroyed, only transformed from one form to another. In this context, the heat energy added to the ice will be converted into thermal energy, which will either increase the temperature of the ice or facilitate its phase change into water, depending on the amount of heat supplied.
Video consigliato:
Percorso guidato
06:24
Conservation Of Mechanical Energy
Pratica correlata
Domanda del libro di testo

The temperature within the Earth’s crust increases about 1.0 C° for each 30 m of depth. The thermal conductivity of the crust is 0.80 J/s C°. Determine the heat transferred from the interior to the surface for the entire Earth in 1.0 h.

906
views
Domanda del libro di testo

A leaf of area 40cm² and mass 4.5 x 10⁻⁴ kg directly faces the Sun on a clear day. The leaf has an emissivity of 0.85 and a specific heat of 0.80 kcal/kgK. Estimate the energy absorbed per second by the leaf from the Sun.

929
views
Domanda del libro di testo

A 12-g lead bullet traveling at 220 m/s passes through a thin wall and emerges at a speed of 160 m/s. If the bullet absorbs 50% of the heat generated, If the bullet’s initial temperature was 20°C, will any of the bullet melt, and if so, how much?

886
views
Domanda del libro di testo

A microwave oven is used to heat 250 g of water. On its maximum setting, the oven can raise the temperature of the liquid water from 20°C to 100°C in 1 min 45 s ( = 105 s).

(a) At what rate does the oven put energy into the liquid water?

(b) If the power input from the oven to the water remains constant, determine how many grams of water will boil away if the oven is operated for 2 min (rather than just 1 min 45 s).

1144
views
Domanda del libro di testo

Calculate what will happen when 1000 J of heat is added to 100 grams of water at 100°C.

659
views