A baseball is thrown by the center fielder (from shoulder level) to home plate where it is caught (on the fly at eye level) by t
he catcher. At what point does the magnitude of the vertical component of velocity have its maximum value? (air resistance is negligible)
1 answer:
At the highest point of the trajectory the vertical component will have its zero velocity, and the descent caused by the force of gravity will begin.
Since the ball is thrown with a certain speed, the vertical component reaches its highest point (upwards), until returning to the receiver who will receive the ball with the same vertical component but in the opposite direction (downwards).
Therefore the vertical component will have its highest value at launch.
You might be interested in
Answer:
0.767
Explanation:
The work done on the truck by the frictional drag force is given by
where
F is the magnitude of the frictional force
d = 38.0 m is the maximum displacement allowed for the truck
The negative sign is due to the fact that the force of friction is opposite to the motion of the truck
The force of friction can also be written as:
where
is the coefficient of kinetic friction between the truck and the lane
m is the mass of the truck
g is the acceleration of gravity
So we can rewrite the work done as
(1)
According to the work-energy theorem, the work done by friction is equal to the change in kinetic energy of the truck:
(2)
where
v = 0 is the final velocity of the truck
u = 23.9 m/s is the initial velocity of the truck
By combining (1) and (2) we get
And solving for , we find the minimum coefficient of kinetic friction able to stop the truck in a distance d:
Answer:
The angular speed of the system increases.
The moment of inertia of the system decreases.
Explanation:
As we know that the girl is going towards the center of the circle so here the moment of inertia of the girl is given as
here we know that
r = position of the girl from the center of the disc
now we know that the girl is moving towards the center so its distance will continuously decreasing
So the moment of inertia of the girl will decrease
Now we know that that with respect to the center of the disc there is no torque on the disc + girl system
So here we can use angular momentum conservation
So we have
since moment of inertia is decreasing for the system
so angular speed will increase