Answer:
The bullet's initial speed is 243.21 m/s.
Explanation:
Given that,
Mass of the bullet, 
Mass of the pendulum, 
The center of mass of the pendulum rises a vertical distance of 10 cm.
We need to find the bullet's initial speed if it is assumed that the bullet remains embedded in the pendulum. Let it is v. In this case, the energy of the system remains conserved. The kinetic energy of the bullet gets converted to potential energy for the whole system. So,
V is the speed of the bullet and pendulum at the time of collision
Now using conservation of momentum as :
Put the value of V from equation (1) in above equation as :

So, the bullet's initial speed is 243.21 m/s.
Answer:
Person B
Explanation:
Person B will hear the frequency that is lower than the B- flat.
Option B is the correct answer.
MKS system gives the following units:
Distance ----- meters
Mass ----- Kilograms
Time ----- seconds
meter is basic unit for length measurement. smaller units are centimeter, millimeter, micrometer, bigger units are kilometer and so on.
kilogram is the basic unit for mass. smaller unit is gram.
second is the basic unit for time. Greater units are minutes, hours, smallest unit are micro second and so on.
Use KE= 1/2mv^2
So...
50,000=(.5)(1,000)v^2
50,000=500 x v^2
Divide 500 on both sides
100 = v^2
Square root both sides to get rid of v^2
Therefore v = 10 m/s