A. True
if cold air is replacing warm air it is a cold front and vice versa.
'N' is labelled 'runoff'. That's when the water is down. Streets are wet, worms come out of the ground, and water flows down the street to the sewer.
Answer:
183333 Pa
Explanation:
The weight of the football player is : 550 N ,thus the force the player exerts on the floor is 550 N
The area of blades in contact with the floor is = 30cm² = 0.003 m²
Pressure = Force / Area
Pressure = 550 / 0.003
Pressure = 183333 Pa
Answer:
(B) the sum total of all matter and energy
Explanation:
Universe comprises of all the matter and energy that exists in space. It contains billions of stars, planets and interstellar matter that is clouds of dust and gas. There is large amount of the empty space in between.
Universe contains stars as many as grains of sand on all beaches on the Earth. These stars are grouped into galaxies. Milky Way is one of the galaxies. Galaxies can be grouped into clusters and super-clusters.
Explanation:
d) Magnetic force is the power that pulls materials together (magnet e. g iron)
an example :how magnet can pick up a coin.
e) frictional force produces when two surfaces are in contact with each other.
effects of friction : I) it produces heat
II) it causes loss in power.