Answer:
When the hammer is in the sun, heat flows by radiation
When you pick up the hammer, heat flows by conduction
Explanation:
As the hammer lies in the sun, heat is transferred to the hammer by radiation. Heat energy reaches the earth from the sun by radiation. Radiation is a mode of beat transfer in which heat is transferred without a material medium.
When you pick up the hammer, heat flows to your hand by conduction because your body is a conductor of heat.
Answer:
They're different - heat and thermal energy. ... The heat, in turn, speeds up the molecules within the pot and the water. If you place a thermometer in the water, as the water heats up, you can watch the temperature rise. Again, an increase in internal energy will result in an increase in temperature.
Answer:
When a body moves in a circle with constant speed , it is said to be in uniform circular motion .
Explanation:
- When an object moves in a circular path , its direction changes at each point .
- This change in direction result in change of velocity (velocity is vector quantity which changes if direction of the object change) .However speed do not change (it is scalar quantity , not affected by Direction)
- The Change in velocity produce acceleration ( a = v - u)
- Hence The object always produce acceleration in uniform circular motion .So, Some force (centripetal force) is needed to keep the object in circular motion.
A. When the substance is in its gaseous state.
<u>Explanation:</u>
When a substance is expanding against its constant volume and pressure, its temperature increases except when the substance is in gaseous state and not in liquid or solid state. So the internal energy increase in the system not only increases and maintaining the volume and pressure of the system remains constant in its gaseous phase. In the first law of Thermodynamics, it is used specifically that to especially in the case of gaseous system.
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Answer:
Crushing a can.
Melting an ice cube.
Boiling water.
Mixing sand and water.
Breaking a glass.
Dissolving sugar and water.
Shredding paper.
Chopping wood.
