Answer:
1. The bird close to the center
2. 4/25 of the original force.
Explanation:
1. Tangential velocity is v=w*d (in m/s), where w is the rotational speed, commonly denoted as the letter omega (in radians per second). d is the distance from the center of the rotating object to the position of where you would like to calculate the velocity (in meters).
As we can note, the furthest from the center we are calculating the velovity the higher it is, because the rotational velocity is not changing but the distance of the object with respect to the center is. If v=w*d, then the lower the d (distance) the lower the tangential velocity.
2. Take a look at the picture:
We have the basic equation for the gravitational force.
We have to forces: Fg1, which is the original force, and Fg2, the force when the mass and the distance changes.
If we consider that mass 2 didn't change (m2'=m2), mass 1 is four times its original (m1'=4*m1) and distance is 5 times the original (r'=5*r), then next step is just plugging it into the equation for Fg2.
Dividing the original force Fg1 by the new force Fg2 (notice you can just as well do the inverse, Fg2 divided by Fg1) gives us the relation between the forces, cancelling all the variables and being left only with a simple fraction!
Answer: mechanical efficieny.
Efficieny is also expressend as percent. The formula for mechanical efficiency as percent is the ratio work output to wor input times 100.
The ideal mechanical efficiency for a machine would be 1 or 100% which means that all the input work is converted into output work. But this is just an idealization as the friction and other losses of energy make it imposible to reach 100% efficiency in reality, so the mechanical efficiency of real machinces is less than 100% or 1.
Answer:v=0.4 m/s
Explanation:
Mass hockey player 
mass of cup 
Velocity of cup 
let v be the velocity of the combined system
Conserving momentum




Answer:

Explanation:
We are asked to find the final velocity. We are given the acceleration, time, and initial velocity, so we can use the following kinematics formula.

In this formula,
is the final velocity,
is the initial velocity,
is the acceleration, and
is the time.
The bicycle has an initial velocity of 5.0 m *s⁻¹ or m/s, acceleration of 2 m/s², and a time of 5 seconds.

Substitute the values into the formula.

Solve inside the parentheses.

Add.

The units can also be written as:

The bicycle's final velocity is 15 meters per second.