Answer:
a. 18.13m/s
b. 0.84m
c. 2.4m
Explanation:
a. to find the speed at which the ball was lunched, we use the horizontal component.Since the point distance from the base of the ball is 24m and it takes 2.20 secs to reach the wall,we can say that
t=distance /speed

Hence the speed at which ball was lunched is 18.13m/s
b. from the equation

the vertical distance at which the ball clears the wall is
y=8.14-7.3=0.84m
c. the time it takes the ball to reach the 6.2m vertically

the horizontal distance covered at this speed is

D !.!.!.!.!.!!.!.!.!.!.!.!.!.!.!.!.!.!.!.!.!.!.!!..!!..!
Explanation:
It is given that,
Kinetic energy of the electron, 
Let the east direction is +x direction, north direction is +y direction and vertical direction is +z direction.
The magnetic field in north direction, 
The magnetic field in west direction, 
The magnetic field in vertical direction, 
Magnetic field, 
Firstly calculating the velocity of the electron using the kinetic energy formulas as :



(as it is moving from west to east)
The force acting on the charged particle in the magnetic field is given by :


Since, 
And, 
![F=1.6\times 10^{-19}\times [1178 k-2864.20j]](https://tex.z-dn.net/?f=F%3D1.6%5Ctimes%2010%5E%7B-19%7D%5Ctimes%20%5B1178%20k-2864.20j%5D)


(b) Let a is the acceleration of the electron. It can be calculated as :



Hence, this is the required solution.
Take into account that density and relative density are given by:

Take into account that the volume associated to each of the given sustances in the table is determined by the Level Difference (because it is the change in the volume of the water of the recipient in which the substance is immersed).
The density of water in kg/m^3 is 1000 kg/m^3.
Due to the density must be given in kg/m^3, it is necessary to express the volumes of the table in m^3 and mass in kg, then, consider the following conversion factor:
1 m^3 = 1000000 ml
1 kg = 1000 g
Then, you obtain the following results:
Brass:

Cooper:
Answer:
b. The normal force between the molecules of the paper is overcome by the contact force of the hands.
Explanation:
The paper molecules are held together by a weak bond. When the student holds the paper on both sides with the center of the paper in between, the student applies two equal forces in the opposite direction of the paper making the paper molecules weaken and separate.