The sun emits electromagnetic radiation so I think they are electromagnetic waves.
Answer:
2. mechanical weathering can produce smaller pieces of rock that have more surface area for chemical weathering to work Explanation:
Mechanical weathering involves activities of living organisms or some geological processes. The bigger rocks are usually reduced to smaller rocks and further reduction might be limited or not posibble mechanically. This reduced rocks now increases the surface area available for chemical weathering; which further reduces the sizes of the rocks below the size range of mechanical weathering. one will recall that the rate of chemical reaction increases with exposed surface area.
Answer: Work Done would remain same.
Let us assume that the velocity is constant while taking the load up the inclined plane. Then, the kinetic energy would remain the same. This is because kinetic energy is dependent on velocity 
. If that is constant, the kinetic energy would remain same. The potential energy is dependent on the height
. If the height is changed, then potential energy varies. In the question, it is mentioned that without changing the height, the length of the inclined plane is changed. Therefore, the potential energy would be same as before.
We know, work done is equal to potential energy plus kinetic energy. Since there is no change in any of these, the required work done would not change.
Answer: 10Nm or 10J
Explanation:
Given the following :
Force (f) = 5
Distance (d) = 2m
Calculate the kinetic energy assuming no friction
Work done = force × distance
Work done = 5N × 2m = 10Nm
Recall :
Work done = ΔK.E ( change in kinetic energy)
Therefore, kinetic energy of the book after sliding = ΔK. E, which is equal to work done.
Hence, K. E of book after sliding is 10Nm
