Answer:
1. the force which can be felt or act only when two objects are in contact is known as contact force.
for example: frictional force, muscular force,
tension, air resistance .
2. the force which can be felt or act even when two objects are in contact or not is known as non-contact force.
for example: magnetic force, gravitational force, electrostatic force.
Answer: 1.13 X 10^3 g or 1130 g
Explanation: When you add up everything, you will get 1134.1288 g = 1.11341218 X 10^3. But while adding significant figures, we always look for the least significant figures (here 4.65 has least sig. figures i.e. 3) and take that as a reference to how many significant figures we should have in the answer. (Pretty hard to explain!) Hope you got it!!
Answer:
Energy transition therefore occurs due to the amount of kinetic energy gained by the electrons. The electrons with higher kinetic energy are excited to the higher level (excited state) compare to the electron with low kinetic energy (this energy are energy in the ground state)
Explanation:
Energy level transition occur when light rays strikes a metal surface to emit electron from the surface, a term known as photoelectric effect. This amount of electron emitted from the surface depends on the speed of light ray striking the metal surface.
Energy transition therefore occurs due to the amount of kinetic energy gained by the electrons. The electrons with higher kinetic energy are excited to the higher level (excited state) compare to the electron with low kinetic energy (this energy are energy in the ground state)
Answer:
B) 3.50 m/s
Explanation:
The linear velocity in a circular motion is defined as:
The angular frequency (
) is defined as 2π times the frequency and r is the radius, that is, the distance from the center of the circular motion.
Replacing (2) in (1):
We have to convert the frequency to Hz:
Finally, we calculate how fast is the child moving:
were solving for v velocity of the ball after it has hit the bottle. a. momentum ->p=mv->ball + bottle momentum during hit = ball + bottle momentum after hit-> ball (.5*21)+ bottle (.2*0) (it's 0 because the the bottle is standing still) = ball after hit (.5*v)+bottle after hit (.2*30) -> 10.5+0=.5v+6 ->4.5=.5v->v=9m/s
b. if bottle was heavier the ball would be slower so final velocity would decrease
