<h2>
Answer:</h2>
<h2>
Cohesion </h2>
Is the attraction that molecules have for others of their same type.
<h2>
Adhesion </h2>
Is the attraction that molecules have for others of different type by intermolecular forces.
A good example of both is water that can stick to itself through hydrogen bonds (cohesion) and can also stick to a glass due to adhesion.
So, while Cohesion is the force of attraction between adjacent particles within the same body, Adhesion is the interaction between the surfaces of different bodies.
because a chemical change takes time
Answer:
The degree of reflection whether faint or bright you see on the surface of an object is an indication that light particles had hit the surface. Since light is a wave and as part of its characteristics can get reflected. However, the amount of light reflected by a surface is dependent on the smoothness of the surface which can be shiny or dull, it can also be dependent on the nature of the surface which can be glass, water, and so on. So, from the question, you can see a faint reflection on the surface of a shiny plate or cup because of the smoothness of the surface which reflects the lights that hit it from a particular direction at the same angle.
Answer:
Energy, 9 kWh or 32400 kJ
Explanation:
Given that,
The power of heater, P = 3 kW
It runs for 3 hours to raise the water temperature to the desired level. We need to find the amount of electric energy used. We know that the electrical power of an object is given by total energy delivered per unit time. It is given by :
E = 9 kWh
Since, 1 kWh = 3600 kJ
E = 32400 kJ
So, the amount of electric energy used is 9 kWh or 32400 kJ. Hence, this is the required solution.
Answer:
Speed of block after the bullet emerges = 1.5 m/s
Explanation:
Here momentum is conserved.
Initial momentum = Final momentum.
Mass of bullet = 10 g = 0.01 kg
Initial Velocity of bullet = 300 m/s
Mass of block = 1 kg
Initial Velocity of block = 0 m/s
Final Velocity of bullet = 50% of initial velocity. = 150 m/s
We need to find final velocity of block. Let it be v
We have
Initial momentum = 0.01 x 300 + 1 x 0 = 3 kg m/s
Final momentum = 0.01 x 150 + 1 x v = 1.5 + v
Equating
3 = 1.5 + v
v = 1.5 m/s
Speed of block after the bullet emerges = 1.5 m/s
