Answer:
955.5N
Explanation:
The normal force is given by the difference between the centripetal force and gravity at the top of the loop:

mass m = 65kg
radius of the loop r = 4m
velocity v = ?
g = 9.8 m/s²
To find the centripetal force, you need to find the velocity of the car at the top of the loop.
Use energy conservation:

At the top of the hill:

At the top of the loop:

Setting both energies equal and canceling the mass m gives:

Solving for v:

Using v in the first equation:

Answer:
Single replacement
Explanation:
A reaction in which one element replaces a similar element is called single replacement. In this case, C is replacing A.
Answer:
the magnitude of the velocity of one particle relative to the other is 0.9988c
Explanation:
Given the data in the question;
Velocities of the two particles = 0.9520c
Using Lorentz transformation
Let relative velocity be W, so
v
= ( u + v ) / ( 1 + ( uv / c²) )
since each particle travels with the same speed,
u = v
so
v
= ( u + u ) / ( 1 + ( u×u / c²) )
v
= 2(0.9520c) / ( 1 + ( 0.9520c )² / c²) )
we substitute
v
= 1.904c / ( 1 + ( (0.906304 × c² ) / c²) )
v
= 1.904c / ( 1 + 0.906304 )
v
= 1.904c / 1.906304
v
= 0.9988c
Therefore, the magnitude of the velocity of one particle relative to the other is 0.9988c
Answer: the earth
Explanation: ask your teacher
Utilize the formula: 
= Final Velocity (86 m/s)
= Initial Velocity (0 m/s)
a = acceleration (m/s²)
t = Time (100 seconds)
As a result,
86 m/s = 0 + (a)(100 seconds)
Using algebra, divide 86 m/s by 100 seconds:
86 m/s = 100a
a = 0.86 m/s²
Rounded to one decimal place: 0.9 m/s²
Let me know if you have any questions!