B. walking
C. swimming
D. all of the above
Answer:
D. All of the above
Explanation:
Newton's third law states that:
"when an object A exerts a force on an object B, object B exerts an equal and opposite force on object A. These forces are called action and reaction"
Let's analyze each situation:
A. when hitting a baseball with a bat --> we have two objects (the baseball and the bat), so we have a pair of forces: the action is the force exerted by the baseball on the bat, while the reaction is the force exerted by the bat on the baseball
B. walking --> in this case, the two objects we should consider are the man walking and the road: the action is the force exerted by the feet of the man on the road, while the reaction is the force exerted by the road on the feet of the man, which allows him walking
C. swimming --> in this case, the two objects we should consider are the man swimming and the water around him: the action is the force exerted by the body of the man on the water, while the reaction is the force exerted by the water on the body of the man, which allows him to swim.
So, all the three choices are correct.
The speed of the electron before reaching the positive plate is
Explanation:
As per Gauss law of electro statistics, the electric field generated by a capacitor is directly proportional to the surface charge density of the plate and inversely proportional to the dielectric constant. In simple words, the electric field is proportional to the surface charge density. So,
And then from the second law of motion,
So acceleration exerted by the electrons will be directly proportional to the force exerted on them and inversely proportional to the mass of the electron.
Since force is also calculated as product of charge with electric field in electrostatic force,
So, the charge of electron
m is the mass of electron which is equal to
Then,
So the acceleration of the electron in the capacitor will be
Then, the velocity can be observed from the third equation of motion.
As u = 0 and s is the distance of separation between two plates.
Thus,
So, the speed of the electron before reaching the positive plate is .
a. True
b. False