Answer:
when it reduces heat.
Explanation:
Thermal energy is transferred to material,the motion of its particles speeds up and it's temperature differences.Insulating materials are bad conductors and so this reduces the heat loss by conduction.The material also prevents air circulating inside the cavity,therefore reducing heat loss by convection.Heat loss through the roof can be reduced by laying loft insulation.
Answer:
E = 3 × 10¹⁰ J
Explanation:
Mass, m = 100 kg
We need to find energy made by the loss of 100 kg of mass. The formula between the mass and energy is given by :
E = mc²
Where c is speed of light
Putting all the values, we get :
E = 100 kg × (3×10⁸ m/s)²
= 3 × 10¹⁰ J
So, the required energy is 3 × 10¹⁰ J.
Answer:
Dana filtered the sample and larger granules of the sample were left behind.
Explanation:
If a substance is pure, it will have a uniform composition throughout. It will not separate into particles of various sizes.
One of the characteristics of pure substances is that they are homogeneous. A mixture is definitely made up of particles of various sizes.
Since the particles was filtered and larger granules were left behind, the sample has been separated by a physical method (filtration). Only a mixture can be separated by physical methods. It is not a pure substance.
