Answer:
B
Explanation:
Adding a dopant is correct on edge.
 
        
                    
             
        
        
        
Answer:
1472.98 m
Explanation:
Data provided:
Speed of circular looping, v = 340 m/s
Acceleration, a = 8g
here,
g is the acceleration due to the gravity = 9.81 m/s²
Now, 
the centripetal acceleration is given as,
  
r is the radius of the loop 
on substituting the respective values, we get
 
or
r = 1472.98 m
 
        
             
        
        
        
Answer:
e) 120m/s
Explanation:
When the ball reaches its highest point, its velocity becomes zero, meaning
 .
.
where  is the initial velocity.
 is the initial velocity.
Solving for  we get
 we get 
 
 
which is the time it takes the ball to reach the highest point.
Now, after the ball has reached its highest point, it turns around and falls downwards. After time  since it had reached the highest point, the ball has traveled downwards and the velocity
 since it had reached the highest point, the ball has traveled downwards and the velocity  it has gained is
 it has gained is 
 ,
,
and we are told that this is twice the initial velocity  ; therefore,
; therefore, 

which gives

Thus, the total time taken to reach velocity  is
 is 


This  , we are told, is 36 seconds; therefore,
, we are told, is 36 seconds; therefore, 

and solving for  we get:
 we get: 



which from the options given is choice e. 
 
        
             
        
        
        
Answer:
Option C
Explanation:
v= u + at
20 = 5 + a(5)
15= a(5)
a= 3 m/s²
Force = mass × acceleration
= 10 × 3
= 30 N
 
        
             
        
        
        
Please ignore my comment -- mass is not needed, here is how to solve it. pls do the math 
at bottom box has only kinetic energy 
ke = (1/2)mv^2 
v = initial velocity 
moving up until rest work done = Fs 
F = kinetic fiction force = uN = umg x cos(a)
s = distance travel = h/sin(a)
h = height at top 
a = slope angle 
u = kinetic fiction 
work = Fs = umgh x cot(a) 
ke = work (use all ke to do work) 
(1/2)mv^2 = umgh x cot(a) 
u = (1/2)v^2 x tan (a) / gh