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.
When an object is moving around in circles, there are two forces that keeps it in its circular orbit. These are the centripetal and the centrifugal forces. They are equal in magnitude, but they differ in the direction. The centripetal force is the force that pulls the object toward the circle's center. The centrifugal force is the force that pushed the object away from the circle's center.
Applying Newton's Second Law of Motions, any force is equal to its mass times its acceleration. For an object moving in circles, the force here is centrifugal or centripetal force, and the acceleration is the centripetal or centrifugal acceleration which is equal to
a = v²/r,
where v is the linear or tangential velocity
r is the radius of the circle
Applying this to Newton's Second Law of Motion,
F = mv²/r
Substituting the values,
F = (1,520 kg)(24 m/s)²/455 m
F = 1,924.22 N
Let d = distance that the fugitive travels to get on the train.
Let t = the time to travel the distance d.
The fugitive starts from rest accelerates at a = 3.8 m/s².
Therefore
(1/2)*(3.8 m/s²)*(t s)² = (d m)
1.9 t² = d (1)
The train travels at constant speed 5.0 m/s.
Therefore
(5.0 m/s)*(t s) = d
5t = d (2)
If the fugitive successfully boards the train, then equate (1) and (2).
1.9t² = 5t
t = 0 or t = 2.6316 s
Ignore t = 0, so t = 2.6316 s.
The speed of the fugitive after 2.6316 s, is
v = (3.8 m/s²)*(2.6316 s) = 10 s
This speed exceeds the maximum speed of the fugitive, therefore the fugitive fails to get on the train.
Answer: The fugitive fails to get on the train.
A. Gravity..... is ur answer