Answer:
D and A
Explanation:
Hint The basic difference between them is that a bar magnet is a permanent magnet whereas an electromagnet is a temporary magnet. An electromagnet is formed when an electric current is passed through wires wound around soft metalcore. An electromagnet loses its magnetism once the current flow is stopped.
a) El Niño is defined as an abnormal weather pattern caused by the warming of the Pacific Ocean near the equator, off the coast of South America. The sun warms the water near the equator, which can make more clouds and, therefore, more rain. It has detrimental effects on biodiversity leading to its large-scale loss by
warmer sea temperatures leading to plankton and fish kills in coastal waters
lower sea levels leading to exposure of underwater coral reefs, causing their loss.
Answer:
Part a)

Part b)

Part c)


Explanation:
Part a)
As we know that frequency = 1 MHz
speed of electromagnetic wave is same as speed of light
So the wavelength is given as



Part b)
As we know the relation between electric field and magnetic field



Part c)
Intensity of wave is given as



Pressure is defined as ratio of intensity and speed


Average speed = total distance / time ⇒ total distance = average speed * time
Average speed = 270 km / p hours
distance = d
hours = x
d = 270/p * x
Answer:
Sliding Friction
Explanation:
The term sliding friction refers to the resistance created by two objects sliding against each other. This can also be called kinetic friction. Sliding friction is intended to stop an object from moving.