Determine the kinetic energy of a 1000-kg roller coaster car that is moving with a speed of 20.0 m/s.
1 answer:
You might be interested in
The average velocity is 20 km/h west
Explanation:
The velocity of an object is given by:
where
d is the displacement
t is the time elapsed
The displacement of an object is a vector connecting the initial position and the final position of motion.
In this problem, the car moved
40 km East
80 km West
Therefore, the displacement is given by (taking West as positive direction)
West
The time elapsed is
t = 2 h
Therefore, the average velocity is
in the West direction.
Learn more about average velocity:
#LearnwithBrainly
a) The angular velocity of the electron is
b) The number of revolutions per second is rev/s
c) The centripetal acceleration of the electron is
Explanation:
a)
This is a problem of uniform circular motion: in fact, the electron orbits around the proton in a uniform circular motion.
The angular velocity of an object in uniform circular motion is given by
where
v is the linear speed
r is the radius of the trajectory
For the electron orbiting around the proton, we have
Therefore, the angular velocity is
b)
The period of revolution of the electron is given by
where
is the angular velocity
Substituting,
The period is the time the electron takes to make one complete orbit around the proton; therefore, the number of revolutions of the electrons in one second is:
rev/s
c)
The centripetal acceleration of an object in circular motion is
where
v is the linear speed
r is the radius of the circle
For the electron, we have
Therefore, the centripetal acceleration is
Learn more about circular motion:
#LearnwithBrainly