Answer:
15.7 m/s
Explanation:
The motion of the cannonball is a accelerated motion with constant acceleration g = 9.8 m/s^2 towards the ground (gravitational acceleration). Therefore, the velocity of the ball at time t is given by:

where
u = 0 is the initial velocity
g = 9.8 m/s^2 is the acceleration
t is the time
If we substitute t=1.6 s into the equation, we find the final velocity of the cannonball:

Answer:

Explanation:
Given:
- mass of car,

- distance of skidding after the application of brakes,

- coefficient of kinetic friction,

<u>So, the energy dissipated during the skidding of car:</u>
<em>Frictional force:</em>

where N = normal reaction by ground on the car


<em>Now from the work-energy equivalence:</em>


is the dissipated energy.
Answer:
The value is 
Explanation:
From the question we are told that
The mass of the block is 
The force constant of the spring is 
The amplitude is 
The time consider is 
Generally the angular velocity of this block is mathematically represented as

=> 
=> 
Given that the block undergoes simple harmonic motion the velocity is mathematically represented as

=> 
=> 
Answer:
Mass of bike = 38 kg.
Explanation:
Kinetic energy is given by the expression,
, where m is the mass and v is the velocity.
Here speed of child riding bike = 6 m/s
Mass of child = 30 kg
Total kinetic energy = 1224 J
Let the mass of bike be, m kg
So, total mass of child and bike = (m + 30) kg
Substituting,

So, mass of bike = 38 kg.