Answer:
B, D,E,F
Explanation:
Situations from the list in which mechanical energy is conserved.
Whenever there is friction there is always some loss of energy in the process and hence energy cannot be conserved.
- The Moon orbiting the Earth (Total energy is remains the same)
- An ice skater gliding along the ice
( smooth surface no friction loss)
- A ball sliding down a friction less hill ( again friction less process)
- A child swinging on a friction less swing, ignoring air resistance
A)float
D)<span>density is greater than the weight of the object
</span>
Answer:
the answer to the question is indeed B
Convection. As the water molecules are being heated up at bottom, the molecules with less heat energy then move to take their place. By doing this all the water should reach an equal temperature.
Answer: A
Explanation:
The air resistance as frictional force will always exist whenever there is motion. And cease to exist whenever there is no motion.
Among all the options, a lamp fixed with a rod from the ceiling experiences no movement. Therefore, this frictional force is ABSENT in that situation.
