Answer:
Explanation:
v = u +at
u = 0
a = 2.3 m /s²
t = 20 s
v = 2.3 x 20
= 46 m /s
Distance covered under acceleration of 2.3 m/s²
s = ut + 1/2 at²
= 0 + .5 x 2.3 x 20²
= 460 m
After that it moves under free fall ie g acts on it downwards .
v² = u² - 2gh , h is height moved by it under free fall
0 = 46² - 2 x 9.8 h
h = 107.96 m
Total height attained
= 460 + 107.96
= 567.96 m
b ) At its highest point ,it stops so its velocity = 0
c ) rocket's acceleration at its highest point = g = 9.8 downwards .
At highest point , it is undergoing free fall so its acceleration = g
Initial velocity (Vi) = 25 m/s
acceleration (a) = 
time interval (t) = 5 sec
let us assume that final velocity after 5 sec be Vf
As acceleration is constant, we can apply the the equation of motion with constant acceleration i.e. 
Hence, 
so, the velocity of bicyclist will be 5 m/s after 5 sec
Actually it's

and it says that the energy of an object (E) is equal to the mass (m) of the object multiplied with the squared speed of light (

). This theory says that mass can be turned into energy and energy can be turned into mass. This is one of Einstein's theory of relativity.
Answer:
B. decreases while his angular speed remains unchanged.
Explanation:
His angular speed will always be the same as the wheel's angular speed, which remains constant as it's in uniform motion. As for linear speed, which is defined as the product of angular speed and distance r to the center of rotation, and his distance to center is decreasing, his linear speed must be decreasing as well.
The force on the object has a constant strength, but its direction
keeps changing. The force is always directed from the object to
the center of the circle. It's called "centripetal force".